feat(agent): import SA-MP Pawn mappings

[ceax3]

Summary

• add safe literal .pwn mapping inspection/import to the CLI and MCP server
• preserve XYZ rotations and apply RemoveBuildingForPlayer as reviewable runtime suppression
• load SA-MP/open.mp object definitions from a user's existing installation without bundling game assets
• index explicit modloader IDE additions and document the workflow and limitations

Validation

• python -m unittest tools.agent.tests.test_samp tools.agent.tests.test_portable_index (10 passed)
• MCP stdio discovery test (1 passed)
• compileall, tabnanny, and git diff --check
• real open.mp asset catalogue: 15,694 models, including SA-MP model 19552 from the generated modloader package
• real Ariane import of sf-gasstation-shop.pwn: 56 objects, 13 removals, 7 full XYZ rotations, then rolled back cleanly

The remaining simulator suite is not runnable with this Windows Python build because socket.AF_UNIX is unavailable; 34 non-simulator tests passed before those existing transport setup errors.

[ceax3]

Closing at the contributor's request.