dynamic_modules: add bool metadata, metadata keys/namespaces, and bool attribute ABI (http)

[kanurag94]

Commit Message: dynamic_modules: add bool metadata, metadata keys/namespaces, and bool attribute ABI
Additional Description: Extends the dynamic modules ABI and SDK (Go + C++) with:

• GetMetadataBool / SetMetadataBool — bool metadata getter/setter
• GetMetadataKeys — Get all keys a metadata namespace
• GetMetadataNamespaces — Get all metadata namespace names
• GetAttributeBool — bool attribute getter (e.g. ConnectionMtls)

Risk Level: Low
Testing: Added C++ unit tests for all new ABI functions + Go integration test extensions. Manually tested with a Go dynamic module against envoy build
Docs Changes: N/A
Release Notes: N/A
Platform Specific Features: N/A
[Optional Runtime guard:] N/A
[Optional Fixes #Issue]: N/A
[Optional Fixes commit #PR or SHA]: N/A
[Optional Deprecated:]: N/A
[Optional API Considerations:] N/A

[repokitteh-read-only]

As a reminder, PRs marked as draft will not be automatically assigned reviewers,
or be handled by maintainer-oncall triage.

Please mark your PR as ready when you want it to be reviewed!

🐱

Caused by: #43537 was opened by kanurag94.

see: more, trace.

[repokitteh-read-only]

CC @envoyproxy/coverage-shephards: FYI only for changes made to (test/coverage.yaml).
envoyproxy/coverage-shephards assignee is @RyanTheOptimist

🐱

Caused by: #43537 was ready_for_review by kanurag94.

see: more, trace.