fix: regenerate local documentation through develop

[Pluze]

Why

The Launcher local-documentation maintenance action could block at “Opening”
because it mixed generation, local opening, online opening, and a synchronous
choice dialog. Repository delivery also allowed a second hotfix route and
accumulated noisy main-to-develop synchronization commits after squash merges.

What changed

• Make Generate Local Documentation rebuild the ignored site/ output from
  current Markdown sources without opening a browser or showing a choice dialog.
• Keep Documentation and History responsible for online reading and retain
  the explicit programmatic local-path lookup for existing generated output.
• Accept main pull requests only from the repository-owned develop branch;
  remove the hotfix exception from executable policy and durable guidance.
• After a merged delivery, require guarded deletion and exact recreation of
  develop at the new main SHA instead of a synchronization commit.
• Advance the Launcher from 1.8.0 to 1.8.1 and record both changes in structured
  history.

Evidence

python3 .github/scripts/test_check_integration_policy.py
  5 tests passed

python3 .github/scripts/check_integration_policy.py \
  --event-name pull_request --base-ref main --head-ref develop \
  --head-repository Pluze/LabKit-MATLAB-Workbench \
  --repository Pluze/LabKit-MATLAB-Workbench \
  --base-sha origin/main --head-sha HEAD
  Integration policy passed

MATLAB R2025a: Launcher exact source-aligned closure
  41 tests passed

MATLAB R2025a: buildtool changedFast
  56 selected identities passed

MATLAB R2025a: buildtool docsCheck
  377 generated files deterministic

No native browser interaction requires manual validation: the generation action
no longer opens one. Full cross-platform and release-boundary validation remains
owned by required PR CI.

Risks and follow-up

Local documentation generation remains synchronous so completion is reported
only after all files exist. Recreating protected develop requires temporarily
allowing deletion; the procedure must stop unless all develop work is merged and
no open PR depends on it, and protection must be restored immediately.

No scientific calculations, App project data, file formats, runtime
dependencies, or release tags change.

Author confirmation

• The final diff matches the stated scope and contains no unrelated change.
• The evidence above covers required local and manual validation; every
  remaining unverified boundary is explicit.
• The diff contains only synthetic or generic public data, with no private
  App details, lab identifiers, local paths, or recognizable sample values.