The attached class should provide what you are looking for based on my testing.  This follows work I did while at a prior position.

Some things to note about this class

• I'm declaring SqlRowIdName = Id so that I don't end up with an Id1 column in the SQL view of the table
• I've set Parameter STORAGEDELIMITERCHECK = 1; so that when an Save/Insert/Update is done it ensures that the data fields do not contain a delimiter and then "throw off" the piecing strategy, if you aren using delimited data but instead using $list data then you wouldn't need this.
• I've overridden %OnNew so as to establish an array of namespaces where the data lives
• You would also want to call SetServerInitCode in %SYSTEM.SQL or the corresponding SetOption in %SYSTEM.SQL.Util  so as to build up the namespaces array.
• My usage of the namespaces array is for demonstration purposes only, your application probably already has some array that defines where the CB global is defined.
• If you want to only provide read access thru objects and SQL you could set the class Parameter READONLY=1;

seems like uploading a file doesn't work.. here's the class definition .. this will work on Cache or IRIS although on a Cache based system you would have to change <Type>%Storage.SQL</Type> to the proper Cache type.

Class Mapping.Test1 Extends%Persistent [ SqlRowIdName = Id, StorageStrategy = SQLStorage ]
{

/// NamespaceProperty NS As%String [ Required ];/// Contact Row IDProperty RowID As%Library.String(SELECTIVITY = 1, TRUNCATE = 1) [ Required ];Property Field1 As%String;Property Field2 As%String;

Index RowIDBasedIDKeyIndex On (NS, RowID) [ IdKey ];/// <Example>/// Set tSC=##class(Mappting.Test1).Populate()/// </example>ClassMethod Populate() As%Status
{
    #dim tSC 			As%Status=$$$OK#dim eException  	As%Exception.AbstractExceptiontry {
        Set tObject=..%New()
        Set tObject.NS="LAB"Set tObject.RowID=1$$$THROWONERROR(tSC,tObject.%Save())
        Write !,tObject.NS,": ",tObject.RowID
        
        Set tObject=..%New()
        Set tObject.NS="ARK"Set tObject.RowID=1$$$THROWONERROR(tSC,tObject.%Save())
        Write !,tObject.NS,": ",tObject.RowID
        
        &SQL(insertinto Mapping.Test1 (NS,Rowid) values ('LAB',2))
        If SQLCODE $$$ThrowStatus(##class(%Exception.SQL).CreateFromSQLCODE(SQLCODE,%msg))
        
    }
    catch eException {
        Set tSC=eException.AsStatus()
    }
    Quit tSC
}

Storage SQLStorage
{
<SQLMap name="Map1">
<Data name="Field1">
<Delimiter>"^"</Delimiter>
<Piece>1</Piece>
</Data>
<Data name="Field2">
<Delimiter>"^"</Delimiter>
<Piece>2</Piece>
</Data>
<Global>namespaces</Global>
<Subscript name="1">
<Expression>{NS}</Expression>
</Subscript>
<Subscript name="2">
<Expression>1</Expression>
</Subscript>
<Subscript name="3">
<DataAccess>^[{L1}]CB({L2})</DataAccess>
<Expression>{RowID}</Expression>
</Subscript>
<Type>data</Type>
</SQLMap>
<StreamLocation>^Mappting.Test1S</StreamLocation>
<Type>%Storage.SQL</Type>
}

/// This callback method is invoked by the <METHOD>%New</METHOD> method to /// provide notification that a new instance of an object is being created./// /// <P>If this method returns an error then the object will not be created./// <p>It is passed the arguments provided in the %New call./// When customizing this method, override the arguments with whatever variables and types you expect to receive from %New()./// For example, if you're going to call %New, passing 2 arguments, %OnNew's signature could be:/// <p>Method %OnNew(dob as %Date = "", name as %Name = "") as %Status/// If instead of returning a %Status code this returns an oref and this oref is a subclass of the current/// class then this oref will be the one returned to the caller of %New method.
Method %OnNew() As%Status [ Private, PublicList = namespaces, ServerOnly = 1 ]
{
    
    #dim tSC		As%Status=$$$OK#dim eException	As%Exception.AbstractExceptionTry {
        Set namespaces("LAB")=""Set namespaces("ARK")=""
    }
    Catch eException {
        Set tSC=eException.AsStatus()
    }
    Quit tSC
}

Parameter STORAGEDELIMITERCHECK = 1;

}

Not sure of your specific question but I have always considered having ReportDefinition not sort the data but instead implement ordering as part of the ReportDisplay when using a <table>.  orderby in a table performs an xsl sort and feel like it's the better place to perform this so that I'm not asking the database to perform the ordering.

In this case I think tSC represents a status that indicates was the HttpRequest able to reach the remote server, not specifically what the call successful or not and yes

http.HttpResponse.StatusCode 

will have values of 

200 

401

404

500

etc.

if you are already using Twilio they have a simple REST API that you could invoke while in IRIS.

This information is found in the class

Ens.ServiceRegistry.External.Service

You wrote

The module.xml has the one line which describes unit tests:

<UnitTest Name="src" Package="UnitTests" Phase="test"/>

This line means that  ZPM will look in /src folder of the repo and will run all the tests of all the classes which are included in UnitTests packageIs 

Is this to say the Name="src" means it will look on the machine where the module has been installed in the /src folder?  If this is so this is problematic for us I believe.  We are trying to protect our IP and as part of the Module.xml definition we have 2 Invokes that help with this effort

1. <Invoke Class="RCIPM.Utils" Method="MakeModuleDeployed" Phase="Compile" When="After" CheckStatus="false">  We do this because there are some classes which cannot be marked as Deployed as they need to be compiled additional times on the application namespaces after we have run the install command in HSCUSTOM

2.  <Invoke Class="RCIPM.Utils" Method="DeleteModulesFolder" Phase="Activate" When="After" CheckStatus="true">

If we don't delete the Module folder then our classes are there in plain text and could be lifted off of the server.

so if Name="src" mean look in the /src folder on the target machine(not the registry) then this wouldn't work for us.

That's not to say that DeleteModulesFolder doesn't cause other issues but its currently what we feel we need to do to protect our code.

Regarding

If the first bullet item in the Query Plan is “Read master map”, or the Query Plan calls a module whose first bullet item is “Read master map”, the query first map is the master map rather than an index map. Because the master map reads the data itself, rather than an index to the data, this almost always indicates an inefficient Query Plan. Unless the table is relatively small, we should create an index so that when we rerun this query the Query Plan first map says “Read index map.”

I think it's more subtle than that.  My general plan of attack is to review the results of Show Plan and then search for Looping.  If the first bullet item in Show Plan is one of the following

• Read master map Ens.MessageHeader.IDKEY, using the given idkey value.
• Read master map Ens.MessageHeader.IDKEY, looping on ID (with a range condition).

I'm not immediately concerned.  In the first case this is going directly to the row which is perfectly fine.  

In the second case so long as the range condition is not going to read the entire extent I can accept that and not look for a better query plan.

Honestly, where its 

Read master map Ens.MessageHeader.IDKEY, looping on ID (with a range condition).

or

Read index map Ens.MessageHeader.TimeCreated, looping on TimeCreated (with a range condition) and ID.

I don't care if its the master map or the index map, what I'm interested in is Looping and does looping cause the engine to look at the entire extent or index.

Still not fully able to grasp what you are doing but if are trying to address 

log.cls_id IN (61) AND log.q_id IN (19, 25, 27)

I often find myself doing something like

log.cls_id %INLIST $LISTFROMSTRING(':Param1,',')

AND log.q_id %INLIST $LISTFROMSTRING(':Param2,',')

and then set Param1=61 and Param2 = "19, 25, 27"

so long as you know the values of Param1 and Param2. 

%INLIST is documented https://docs.intersystems.com/iris20241/csp/docbook/Doc.View.cls?KEY=RS…

and

$LISTFROMSTRING is documented here https://docs.intersystems.com/iris20241/csp/docbook/Doc.View.cls?KEY=RS…

Is this a CSP class or a class that extends from %ZEN.Component.page, it looks like you might be have a CSP page that wants to use ZEN components and do not think that is possible.. but I could be incorrect.  Regardless, is the &html ON LINE 72 closed with the > symbol on line 92?

some thoughts on using custom ZEN Components that I follow that might help.

1. In my custom component I have 

   ///  If true, then the include files generated for this component, are placed in the///  common /csp/broker directory and not the local /csp/*namespace* directory.<br/>///  This is intended for use with packages that are mapped so as to be visible to every namespace.<br/>///  All Zen classes within the same package must have the same value for this parameter.///  It is the developer's responsibility to ensure this.Parameter USECOMMONDIRECTORY As BOOLEAN = 1;

   and

/// XML namespace for component.Parameter NAMESPACE = "http://www.readycomputing.com/zen";

2. In my ZEN page in 

<page xmlns="http://www.intersystems.com/zen" xmlns:RC="http://www.readycomputing.com/zen"

if you are using Package Mapping with a common database for your classes I found using USECOMMONDIRECTORY neccessary.