feat(text): bounded name similarity for application suggestions

[zackees]

Scope

Refs #184. Adds text-similarity, an opt-in facade-owned name_similarity operation with private exact strsim0.11.1. Fixed UTF-8 byte and Unicode scalar-product bounds reject excessive storage/work before scoring. No normalization, candidate selection, ranking or prompt policy moves upstream.

Validation

Observed RED unresolved kernal_api::text, then three focused tests GREEN. Full feature suite passes serially, default-feature check passes, strict all-target Clippy and formatting pass, and compilation-boundary RED -> GREEN checks pass. The broad test first attempt terminated with a Soldr relay failure; retry passed without a source workaround. One reviewer checked Rust/Python/CI/docs plus downstream adoption and found no source findings.

Coordination

Coordinated with FastLED/cli#242. Depends on #183; stacked until that branch lands. FastLED removes direct strsim, keeps substring preference and stable ties, and explicitly propagates resource errors through now-fallible matching helpers. Its full workspace tests, strict all-target Clippy, Python28pass1skip and Ruff pass locally. Publication and exact published adoption remain required before closing #184. No build-speed improvement is claimed.

[zackees]

Application adoption is pushed as FastLED/cli@423761c in draft PR242; both PR bodies link the dependency. Review is clean including the final migration checkpoint. Extracted text-similarity package verification is running. This does not complete issue184 or the full migration: platform CI, publication and exact version consumption remain required.

[zackees]

Extracted-package verification passed: soldr cargo package --locked --features text-similarity -j1, 244 files, 3.0 MiB / 765.8 KiB compressed. This verifies the packaged feature graph locally; publication and platform CI remain separate requirements.