Fix empty Tools collection when loading PromptAgent from YAML

[Copilot]

YamlDotNet 16.x deserializes nested YAML mappings as Dictionary<object, object>, but the generated LoadXxx collection methods only matched on Dictionary<string, object?>, causing all collection-type properties (tools, bindings, parameters, etc.) to be silently empty after YAML deserialization.

Changes

• utils.cs.njk — Added NormalizeDictionary and NormalizeValue extension methods to Utils that recursively convert Dictionary<object, object> → Dictionary<string, object?>, including nested values and lists.

• file.cs.njk — Updated the generated LoadXxx collection template to normalize YamlDotNet dicts at method entry, and added an else if (item is Dictionary<object, object>) branch in the list-item loop.

These two template changes are applied automatically to all generated collection loaders: PromptAgent.LoadTools, Tool.LoadBindings, AgentManifest.LoadResources, ContainerAgent.LoadProtocolVersions, ObjectProperty.LoadProperties, PropertySchema.LoadProperties.

// Before — silently returns empty list from YAML
if (data is Dictionary<string, object?> dict) { ... }
else if (data is IEnumerable<object> list) { ... }

// After — normalizes YamlDotNet's dict type, handles both formats
if (data is Dictionary<object, object> rawYamlDict)
    data = rawYamlDict.NormalizeDictionary(); // recursive normalization

if (data is Dictionary<string, object?> dict) { ... }
else if (data is IEnumerable<object> list)
{
    // list items also normalized
    else if (item is Dictionary<object, object> yamlItemDict)
        result.Add(T.Load(yamlItemDict.NormalizeDictionary(), context));
}

• PromptAgentToolsYamlTests.cs — Adds regression tests covering dictionary-format and list-format tools YAML deserialization.

[sethjuarez]

Hmmm - super important to remember that the CSharp code is generated from the emitter - we may need to update the template files for the emitter - @copilot - can you take that line of inquiry please?

[kerbybarrett]

Any plans to review/merge this? I currently have a locally cloned version of the c# code with my own fix, which is ... less than ideal. Or are there plans to leverage anything coming out of Foundry roadmap for canonical agent schema perhaps?