Fix docs-deploy: add permissions block to Documentation caller job

[ChrisRackauckas-Claude]

Problem

The docs build passes, but the deploydocs push to gh-pages fails (403 / GITHUB_TOKEN cannot push).

Root cause

The CI-centralization migration (centralizing on the SciML reusable documentation.yml@v1) dropped the permissions: block from the .github/workflows/Documentation.yml caller job.

The reusable workflow declares no permissions of its own and deploys via:

GITHUB_TOKEN: ${{ inputs.github-token || secrets.GITHUB_TOKEN }}
DOCUMENTER_KEY: ${{ inputs.documenter-key || secrets.DOCUMENTER_KEY }}

Because the reusable declares no permissions:, the caller job's permissions flow through to the GITHUB_TOKEN. With no block on the caller, the token is read-only, so Documenter's deploydocs cannot push to gh-pages.

Fix

Add a permissions: block to the caller job:

jobs:
  build:
    permissions:
      actions: write
      contents: write
      statuses: write
    uses: "SciML/.github/.github/workflows/documentation.yml@v1"
    secrets: "inherit"

This mirrors the proven fix in SciML/OrdinaryDiffEqOperatorSplitting.jl#90 exactly.

This repo deploys via GITHUB_TOKEN (no DOCUMENTER_KEY required), so contents: write is what enables the gh-pages push. The docs check is not disabled and warnonly is not set.

Verification

• YAML validated with python3 -c "yaml.safe_load(...)" — parses cleanly; the build.permissions block resolves to {actions: write, contents: write, statuses: write}.
• The actual gh-pages deploy can only be fully confirmed by a real CI run on master (deploydocs only pushes on push events, not PRs). The change is correct by construction by matching the proven Fix small bugs/inconsistencies in GP #90 pattern.

Please ignore until reviewed by @ChrisRackauckas.

[ChrisRackauckas-Claude]

Superseded by SciML/.github#102, which sets permissions: contents: write in the centralized documentation.yml reusable itself — so no per-repo permissions block is needed once v1 is retagged. Closing this in favor of the central fix.