Bump rmcp from 1.8.0 to 3.1.2

[dependabot]

Bumps rmcp from 1.8.0 to 3.1.2.

Release notes

Sourced from rmcp's releases.

rmcp-macros-v3.1.2

Fixed

• emit cache hints from handler macros (#1120)

Other

• upgrade darling and syn (#1138)

rmcp-v3.1.2

Fixed

• (auth) map 401/403 challenges on the SSE GET stream (#1152)
• (sse) loop instead of recursing when skipping SSE events (#1146)
• (auth) preserve issuer trailing slash during discovery (#1145)

rmcp-macros-v3.1.1

Fixed

• emit cache hints from handler macros (#1120)

Other

• upgrade darling and syn (#1138)

rmcp-v3.1.1

Fixed

• emit cache hints from handler macros (#1120)
• expose MRTR state to tool handlers (#1104)
• disambiguate input-required results (#1103)

Other

• make async-trait optional (#1119)

rmcp-macros-v3.1.0

Added

• add strict stateless protocol metadata validation (#1091)

Other

• document the ping utility with examples (#1106)
• complete Tier 1 feature docs and finalize roadmap (#1101)
• (conformance) meeting requirements for tier 1 (#1087)

rmcp-v3.1.0

Added

... (truncated)

Commits

• 02c62ae chore: release v3.1.2 (#1148)
• c345078 fix(auth): map 401/403 challenges on the SSE GET stream (#1152)
• f8e6382 chore(deps): bump taiki-e/install-action from 2.85.7 to 2.85.8 (#1153)
• 8fb3e04 chore(deps): bump github/codeql-action from 4.37.4 to 4.37.6 (#1154)
• 3c8fb2a fix(sse): loop instead of recursing when skipping SSE events (#1146)
• e150d4f fix(auth): preserve issuer trailing slash during discovery (#1145)
• 9a3168a chore(deps): bump taiki-e/install-action from 2.85.6 to 2.85.7 (#1139)
• baac607 chore: release v3.1.1 (#1115)
• f57d585 chore: upgrade darling and syn (#1138)
• 07bcda2 fix: emit cache hints from handler macros (#1120)
• Additional commits viewable in compare view

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Summary by cubic

Upgrades rmcp from 1.8.0 to 3.1.2 and rmcp-macros to 3.1.3 to pick up SSE auth fixes, cache hint emission, and stricter protocol metadata validation. Previously handler macros did not emit cache hints and SSE event skipping recursed; now macros emit cache hints and SSE skipping loops, and 401/403 challenges on the SSE GET stream are mapped correctly.

Review and rollout

• Ensure protocol metadata passes strict stateless validation; update metadata if validation fails.
• Run end-to-end SSE tests; expect 401/403 challenges on the SSE GET stream to surface differently.
• If using handler macros, verify cache hints are produced and consumed as expected; adjust any caching logic.
• Confirm builds after dependency changes (uuid added; base64, darling, syn upgraded; async-trait no longer required by rmcp).

^{Written for commit b55cbe1. Summary will update on new commits.}