chore: move the exact mthds pin to 0.14.0 so pipelex and pipelex-sdk co-install

[lchoquel]

Why

pipelex and pipelex-sdk both pin mthds exactly, so they install together only when they name the same version. pipelex has already moved to mthds==0.14.0 on its dev branch, which left this SDK at 0.13.0 and made the pair unresolvable from source. On PyPI the break is still latent — published pipelex 0.56.0 and pipelex-sdk 0.9.0 both require mthds==0.13.0 — so it arrives the moment a pipelex release carrying the new pin is published. This is the move that keeps the two co-installable, and it reaches consumers at the next pipelex-sdk release.

What changed

The pin, the lock, and a changelog entry — nothing else. No source or test adaptation was needed.

mthds 0.14.0's substantive change is MTHDS_STANDARD_VERSION going from 1.0.0 to 2.0.0, which this SDK never reads: it stamps no crates and ships no manifest. The release's other additions — is_mthds_version_satisfied and the parse_constraint whitespace fix — live in mthds.package.manifest.schema, which nothing here imports. PROTOCOL_VERSION stays at 0.6.0, so the routes and the wire contract are untouched.

The inherited seam is unchanged

This SDK builds on MthdsAPIClient's protected extension surface, so that is the part worth stating explicitly rather than inferring from a three-line diff:

• Every protected member this client extends is still present: _API_PREFIX, _DEFAULT_REQUEST_TIMEOUT_SECONDS, _post_validate, _raise_if_execute_degraded, _send, _url.
• The four overrides (execute, start, start_client, validate) still have base counterparts, so the transitional type: ignore[override] suppressions are still load-bearing — none expired.
• The ruff runtime-evaluated-base-classes dotted paths all still resolve, so the mthds.protocol annotations stay runtime-evaluated.

Every mthds import in this package is under mthds.protocol.* or mthds.runners.api.*, neither of which 0.14.0 touched.

Not breaking for importers, but marked breaking

No symbol was renamed, re-exported, or narrowed, so nothing importing pipelex_sdk has to move. The changelog still marks it breaking, because the pin move narrows what every downstream environment may install.

Checks

make agent-check (pyright 0 errors, mypy clean), make agent-test, plus the two CI gates agent-check omits: make pylint at 10.00/10 and make check-unused-imports. All green, with no test fixture edits.

Closes L-260906-d7e27c

🤖 Generated with Claude Code

https://claude.ai/code/session_01DuEKzDiMDWrABBibqwdFTt

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Summary by cubic

Moves the exact mthds pin from 0.13.0 to 0.14.0 so pipelex and pipelex-sdk co-install again.

• Only the pin, lockfile, and a changelog entry changed; no source or test edits.
• MTHDS_STANDARD_VERSION bump and other 0.14.0 additions are unused here; PROTOCOL_VERSION remains 0.6.0.
• The changelog marks this breaking because the pin narrows installable versions.

Closes L-260906-d7e27c.

^{Written for commit 8075a9b. Summary will update on new commits.}