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

CHANGELOG.md

@@ -15,6 +15,7 @@
 - **Breaking: a canonical file dict nested inside a `Dynamic` input is no longer uploaded.** Such an input is `kind: "unknown"` in the descriptor — the standard's escape hatch — and the walk does not enter it. Uploading on the strength of a `url` key is the value-shape guess this change removes; a caller with a Dynamic input uploads with `upload_file` first and passes the storage URI, which `docs/input-preparation.md` has always prescribed.
 - **`prepare_inputs` accepts the explicit `{concept, content}` input envelope**, not only compact values, closing a parity gap with the JS SDK. An agent that fills an explicit template — the shape the hosted console and MCP hand out — can now hand it straight back; previously every file-bearing envelope position raised `InputPreparationError: Unsupported value at a file input … got dict`. The envelope's `content` is interpreted identically and preserved on output, so the concept annotation rides through to the run.
 - **The documentation is rewritten around the descriptor.** `docs/input-preparation.md` now describes the three call shapes, the signature call, pipe selection and its manifest-only `main_pipe` gap, the envelope, and why the template was the wrong signature source; `docs/architecture.md` follows the removal. It also catches up with v0.9.0, which shipped `output_form` and the `mthds` 0.13.0 bump without touching the docs: the views list is no longer described as having one token, the report's typed fields now include `output_form` and `default_pipe_ref`, and the pipe I/O contracts no longer claim an output carries no schema — 0.13.0 made `json_schema` required there, reversing the reasoning the doc still quoted.
+- **Requires `mthds` 0.14.0 (breaking).** The pin moves from 0.13.0. Nothing in this client changed with it: the release's substantive cut 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 — and the new `is_mthds_version_satisfied` helper and the `parse_constraint` whitespace fix sit 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 move still matters to anyone installing this package: `pipelex` pins `mthds` exactly too and has already moved to 0.14.0, so two exact pins on different versions made the pair unresolvable — this is what lets `pipelex` and `pipelex-sdk` co-install again.
 
 ### Security
 

pyproject.toml

@@ -18,7 +18,7 @@ classifiers = [
 ]
 
 dependencies = [
-  "mthds==0.13.0",
+  "mthds==0.14.0",
   "pydantic>=2.10.6,<3.0.0",
   "typing-extensions>=4.0.0",
   "httpx>=0.23.0,<1.0.0",