feat: initial text-extract v0.1.0 (text.extract@0.1.0)

First real F∆I capability module. Ships as alpha in the store
index — installable, but layout-naive PDF extraction. Bumps to
1.0.0 require either the planned service-mode variant
(host-services-backed pdfium/mupdf) or confirmed-good
extraction quality on a representative document set.

Capability surface:

  Inputs:   document : bytes  (PDF or DOCX)
  Outputs:  extracted : json  (ExtractedDocument)
  Permissions: none — pure in-WASM, no filesystem, no network

Output schema:

  {
    "engine": "pdf-extract" | "zip+quick-xml",
    "engine_version": "<version>",
    "pages": [{ "number": <u32>, "text": <string>,
                "confidence?": <f64>, "bbox?": {x,y,w,h} }]
  }

The optional confidence and bbox fields are reserved for the
future service-mode variant. The host-services infrastructure
that backs pdfium/mupdf does not exist yet (Phase 0.5+); when
it lands, text-extract v0.2.0 will populate these fields without
an API break.

Engines:

  PDF:  pdf-extract 0.7 (pure Rust, MIT-licensed). Single-column
        documents extract reliably. Multi-column or table-heavy
        layouts may produce reordered text — documented in
        README as a known limitation of the in-WASM v0.1.0 path.

  DOCX: ad-hoc parser using the zip and quick-xml crates. Walks
        word/document.xml, concatenates run-level text, inserts a
        newline at each paragraph boundary. Tables, footnotes,
        and embedded objects are not extracted in v0.1.0.

The module is the first reference user of fai-module-sdk. The
public surface is one #[fai_module] function — no wit_bindgen,
no Guest impl, no allow attributes. Testing surface is the same
function via crate-type = ["cdylib", "rlib"]; the SDK macro
gates its WASM glue on target_arch = "wasm32" so host integration
tests work out of the box.

Tests: 6 unit + 3 integration, all green. The DOCX integration
test builds a minimal valid DOCX in memory and verifies the
JSON output schema. PDF integration coverage will land in a
follow-up once a representative test fixture is bundled.

The Forgejo CI workflow clones fai/module-sdk into a sibling
location to satisfy the path-based dev dependency. The path
will switch to a versioned git tag once SDK releases stabilize.

Signed-off-by: flemming-it <sf@flemming.it>

NOTICE

@@ -0,0 +1,15 @@
+text-extract
+Copyright 2026 Flemming.AI
+
+This product includes software developed by Dr. Stefan Flemming
+and contributors (https://flemming.ai/).
+
+------------------------------------------------------------------
+Third-party acknowledgments
+
+PDF text extraction is delegated to the `pdf-extract` crate
+(MIT license) and its dependencies. DOCX extraction uses the
+`zip` (MIT/Apache-2.0) and `quick-xml` (MIT) crates.
+
+Runtime dependencies and their licenses are documented in the
+Software Bill of Materials (SBOM) generated on every release.