[docs]: batched docs cleanup (landing page, links, requirements, nav)

[SolitaryThinker]

Batch of nit-class, pure-factual docs fixes (per the batched-PR policy: grouped for one review session; no behavior changes). Each item below is independent; itemized for line-by-line review. Source audit: docs-role first-boot audit vs main @ 8d89f30d.

Items

• Landing page Key Features refresh (docs/index.md) — [audit HIGH-3] Key Features led with Sliding Tile Attention (archived to sta_do_not_delete; the support matrix itself says VSA is strictly better on main) and omitted VSA/DMD2/QAD/self-forcing/Dreamverse. Rewritten to mirror the README's current feature set with links to each docs page (all 10 link targets verified present); tagline aligned to the README's; unsourced "near linear scaling to 64 GPUs" claim dropped.
• Quickstart OS requirements (docs/inference/inference_quick_start.md) — [audit MED-5] Requirements said Linux-only while the repo ships a maintained MPS install guide; now lists macOS/Apple-silicon alongside Linux. (Windows intentionally not added: no install doc backs it.)
• Python range on the installation hub (docs/getting_started/installation.md) — the hub's requirements block never stated a Python range even though gpu.md and the quickstart both document 3.10-3.12. Now states 3.10-3.12 as the tested and recommended range — deliberately not a support ceiling, since pyproject.toml declares requires-python = ">=3.10" and the lockfile resolves 3.13+ (maintainer review infra/r37; also corrects this PR's earlier framing of [Bug] Failed to install via pip #1490, whose actual failure was OSError: Disk quota exceeded, not wheel incompatibility).
• README training pointer accuracy (README.md) — [audit MED-4] the Key Features bullet promised a "full list of supported models and recipes" at training/overview, which contains no model list; now points at the training workflows there and the support matrix for models.
• Sidebar nav for generated example pages (mkdocs.yml) — [audit MED-8] the inference Examples nav listed 3 pages including an archived one, while the LTX-2.3 example pages that docs/generate_examples.py emits were invisible. Added: Examples Index, LTX-2.3, LTX-2.3 Gradio Demo. All six nav targets verified to be produced by a fresh generate_examples.py run.

Landed separately

• Slack invite unification + Discord removal [audit MED-6] shipped via [docs]: unify community links on the README Slack invite #1643 (merged by the author while this batch was being assembled); this PR was rebased onto that merge, so those hunks no longer appear here.

Not in this batch (and why)

• Wan-VACE推理example #1435 (Wan-VACE): the honest fix is a support-matrix note; that surface is owned by the in-flight [docs]: cover all registered models in the support matrix #1641, so the note landed there (avoids two PRs editing the same file).
• [Bug] Several models hardcode supported attention backends. Causing confusion #1254 docs slice (per-model attention-backend matrix): substantive, not nit-class — backend support is currently declared per-layer and interleaves at runtime (that is the bug reported); publishing a per-model matrix now would codify incorrect behavior as documentation. Deferred until the code-side normalization (implementor-tracked) lands.

Supersedes #1642 (closed).

Test evidence

• pre-commit run --files <changed files>: codespell + PyMarkdown pass.
• Landing-page internal links: existence-checked (10/10).
• Nav additions: generate_examples.py run confirms every referenced page is emitted.

[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.

[mergify]

Merge Protections

🔴 1 of 1 protections blocking · waiting on 👀 reviews and 🤖 CI

	Protection	Waiting on
🔴	PR merge requirements	👀 reviews and 🤖 CI

🔴 PR merge requirements

Waiting for

• #approved-reviews-by>=1
• check-success=full-suite-passed

This rule is failing.

• #approved-reviews-by>=1
• check-success=full-suite-passed
• check-success=fastcheck-passed
• check-success~=pre-commit
• title~=(?i)^\[(feat|feature|bugfix|fix|refactor|perf|ci|doc|docs|misc|chore|kernel|new.?model|skill|skills|infra)\]