Fix Outlook search pagination and bound message payloads

[zhouzhuozhzh-maker]

Summary

• honor Outlook search limits up to a safe 100-message cap and follow opaque Microsoft Graph next links inside one tool call
• deduplicate messages across pages, reject off-origin pagination URLs, and expose explicit returned_count, has_more, and query_complete metadata
• keep search results compact with selected header fields, then add outlook_get_message for reading one chosen full message
• guide the agent to narrow the existing query when the cap is reached instead of repeating or broadening it

Root cause

outlook_search_messages silently clamped max_results=100 to 20, returned the raw @odata.nextLink, and offered no continuation parameter. The model therefore had evidence of another page but no supported way to fetch it, which encouraged repeated overlapping searches. The list request also did not select compact fields.

Validation

• .venv/bin/pytest tests/test_connectors.py -k outlook -q (7 passed)
• .venv/bin/pytest -q (1117 passed, 1 skipped)
• git diff --check

Compatibility and risk

The existing account/ok/data/value response shape remains available. Search results intentionally become summaries; callers can use the new read-only outlook_get_message tool when they need a full body. Pagination is bounded by both message and page limits.

Fixes #465