Add unpublished KDP 1.2 docs with rewritten MCP pages

[mstruebing]

Creates a v1.2 KDP docs tree, copied from v1.1 and not published, with the MCP documentation rewritten and the AI Agent removed.

Ref: https://github.com/kubermatic/developer-platform-mgmt/issues/273

Why

KDP now hosts the MCP server behind a gateway that authenticates each caller with their own platform account (developer-platform#779), so users connect to an endpoint rather than running the server themselves. The 1.1 page describes the opposite, and in a way that would not work if followed:

1.1 says	reality
used "together with a Kubernetes MCP server"	not needed — resource CRUD is built in
"a stateful server"	stateless; every tool takes an explicit workspace path
"at the cost of deploying the server"	the platform hosts it; users add one config entry and log in
no install instructions	needs the endpoint URL, client ID and a pinned callback port

Nothing documented the operator side either: the endpoint does not exist until an admin enables the gateway and adds an identity-provider client.

What

MCP

• platform-users/ai-tooling rewritten: hosted endpoint, ready-to-paste Claude Code and OpenCode configuration, the twelve tools, the workspace-path rule, and what the tools deliberately cannot do (service enablement, Blueprint authoring, logs/exec).
• setup/mcp-gateway (new, operator-facing): chart values, the public PKCE client and trustedPeers cross-client trust the provider needs, verification steps and failure modes.
• Both pages warn about the two settings that must not be changed — the callback port is exact-matched by the provider, and pinning OAuth scopes drops the audience that makes kcp accept the token.

AI Agent removed (second commit)

The developer-platform-ai-agent chart is not part of 1.2, so everything documenting it is gone: the setup/ai-agent page and its screenshots, the quickstart section that deployed it (plus the <OPENAI_API_KEY> prerequisite and the two values files it read), the aiAgent feature block in the dashboard values, and the chart's row and upgrade step in the upgrade guide.

The dashboard's own AI assistance is a different component, configured on the dashboard API via api.config.openaiKey, so the UI Builder and Blueprint pages describing it are untouched.

Versioning

v1.2 is registered commented out in data/products.yaml, the same approach used to stage KubeLB 1.3 (e3b6bc06), so it is reachable by direct link but stays out of the version dropdown, sitemap and llms.txt.

Verification

hack/ci/verify-hugo.sh builds clean with no warnings, and codespell passes. Against the built site:

• v1.2 appears 0 times in sitemap.xml and llms.txt, its pages carry noindex, nofollow, and the version dropdown still offers only v0.9.0 / v1.0 / v1.1.
• The new pages render at /developer-platform/v1.2/platform-users/ai-tooling/ and /developer-platform/v1.2/setup/mcp-gateway/.
• After the removal: every relref and readfile target in the tree still resolves, and nothing references the deleted setup/ai-agent page.

Note that hidden versions get no left sidebar (the theme only renders the nav tree for versions listed in products.yaml); it returns when the version is published.

Before publishing

• Uncomment the v1.2 entry in data/products.yaml (one hunk).
• Bump the chart pins, still at 1.1.0: setup/quickstart (×3 plus the kcp chart) and setup/upgrade (title and table).

[kubermatic-bot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[mstruebing]

/retest

[iammerus]

/lgtm
/approve

[kubermatic-bot]

LGTM label has been added.

Details

Git tree hash: d3b57bde6b05d99b7c5660f38f982bb3a9fa303a

[kubermatic-bot]

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