Add ai_tool object to the ai_operation profile for MCP primitive metadata

[Levaj2000]

Related Issue:

#1728

Description of changes:

Adds a new ai_tool object (extending _entity), referenced optionally from the ai_operation profile, recording the AI capability invoked in an operation — full rationale, field-by-field justification, and open questions are in #1728 (proposed by @terylt and @Levaj2000):

• objects/ai_tool.json (new): primitive kind (type_id: Tool/Resource/Prompt), stable capability identity (uid) vs. call correlation (transaction_uid), provenance (service + transport_id), binding (source_id: MCP/Function/Built-in), declared MCP behavior hints (is_readonly/is_destructive/is_idempotent/is_open_world — descriptions state they are self-declared and unverified), schema fingerprints reusing the fingerprint object, resource fields (uri, mime_type), and MCP 2026-07-28 RC fields (cache_scope_id, cache_ttl, task_uid).
• profiles/ai_operation.json: adds the optional ai_tool attribute, with guidance that observed behavior wins over declared hints when deriving activity_id.
• dictionary.json: 12 new entries (ai_tool, transport/transport_id, is_destructive, is_idempotent, is_open_world, input_schema_fingerprint, output_schema_fingerprint, cache_scope/cache_scope_id, cache_ttl, task_uid); everything else reuses existing dictionary entries.
• CHANGELOG.md: entries under Unreleased → Added → Profiles / Objects / Dictionary Attributes.

Single squashed commit authored by @terylt, co-authored by @Levaj2000, DCO signed-off by both.

Validation status (why this opens as draft): all three changed schema files parse as valid JSON and the diff applies cleanly to current main; a local ocsf-server run has not yet been performed — we'll do that (or lean on CI) before marking ready for review.

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Generated by Claude Code

[github-actions]

Schema Description Review

Automated suggestions for improving description clarity for LLM consumption. These are advisory — not required changes.

Previous Review Status

• ✅ Fixed: type — the In the case of 'Other', it is defined by the event source. clause has been added.
• ✅ Fixed: source_id — the In the case of 'Other', it is defined by the event source and carried by the <code>source</code> attribute. clause has been added.
• ✅ Fixed: CHANGELOG entries now use PR links (pull/1729) rather than issue links.

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Summary

All three issues from the previous review have been addressed. The ai_tool object is well-structured, descriptions are detailed and LLM-friendly, sibling conventions are correctly followed, and the CHANGELOG entries now reference the correct PR URL. No new issues have been introduced.

✅ No description issues found — descriptions look clear for LLM consumption.