Branching strategy selection, cumulative authoring, ++

[shainaraskas]

This PR makes information related to our branching strategies and cumulative authoring approach more visible and does some accuracy edits

Key changes

Page	Changes
✏️ Contribute overview	Update instructions so they're not stack version centric, but instead docs platform centric. Provide clearer hints about finding where your docs are published. Introduce hints about deployment models ("Branches in V3") and refactor cumulative documentation callout.
🆕 Write cumulative documentation	Single page that combines an explanation of the cumulative approach with tagging examples
🆕 Choose a branching strategyl	Add decision-making guidance + workflow example for the two branching strategies, connect to the config instructions
🚚 Content sources	Moved the config page for content sources out of the migration docs and into the primary config docs (we might want to do this with more key docs)
✏️ Migration: new versioning	Pulled out content sources, added basic info about tag processing and deployment models

Pages refactored to pivot from stack version to platform, plus minor changes

Page	Changes
✏️ Contribute on the web	Refactored away from stack version to platform, added cumulative documentation hints, added tagged deployment model warning
✏️ Contribute locally	Add cumulative documentation hints, added tagged deployment model warning

Cleanup, minor changes, warnings

Page	Changes
✏️ Syntax ref: Applies to	Refactored examples into snippets to share between the cumulative documentation doc and this one, added info about how applies_to tags behave in the output (dynamic version #s)
✏️ Add a new repository to the docs	Added a note about deployment models
✏️ Documenting versions and deployment types	Added a warning that this is out of date
✏️ Version content patterns	Added a warning that this is out of date

TODO (future PRs)

• Central version config info in the cumulative docs / deployment models / applies syntax docs (done)
• Fix or remove the /versions/ pages
• General internal docs restructure + cleanup (we could probably remove some migration stuff)

[shainaraskas]

@florent-leborgne @colleenmcginnis I think we talked about only having the serverless: unavailable tag here. wyt

I can extend to the areas that follow the same rule based on what we decide (couple of additional instances in this PR)

[florent-leborgne]

I am quite unsettled on this. Let's choose one approach and revisit later if we get feedback on it. No strong opinion at the moment besides trying to keep the badging minimal

[shainaraskas]

I cut the stack tags for now but they're easy to put back in

[colleenmcginnis]

Thanks for getting this started @shainaraskas! I was only able to get through the pages in the Contribute section so far. I tried to scope my review to the accuracy and clarity of information. I didn't leave comments related to style or grammar.

I might have introduced some scope creep in the pages other than deployment model and cumulative authoring 🙈 but it was helpful to read through all the content together to get a full picture. I'll open separate issues for those comments so this PR doesn't become unmanageable.

[github-actions]

🔍 Preview links for changed docs

• docs/configure/content-sources.md
• docs/contribute/branching-strategy.md
• docs/contribute/cumulative-docs.md
• docs/contribute/add-repo.md
• docs/contribute/index.md
• docs/contribute/locally.md
• docs/contribute/on-the-web.md
• docs/migration/guide/working-in-docs-content.md
• docs/migration/versioning.md
• docs/syntax/applies.md

More links …

• docs/syntax/quick-ref.md
• docs/versions/content-patterns.md
• docs/versions/index.md

[colleenmcginnis]

Looks good! I'd say any more work to be done can be done in a follow up.

[florent-leborgne]

Niceeee