Issue #3586542: Fix documentation staleness — automator-type ID drift,...

Description

Fixes the documentation staleness findings in #3586542. This is a documentation-only change — no code paths are altered.

• Automator-type ID drift: renamed 9 pages so filenames match the real plugin IDs (llm_audio_to_text_with_summary, llm_json_native_field, llm_json_native_binary_field, llm_audio_generation, llm_media_Audio_generation, vector_search_text_long, llm_image_generation, summarize_to_string_long, summarize_to_text_long) and updated the automator index table links.
• Missing pages: added llm_rewrite_image_filename, llm_text_create_summary, and views_extract_text_long (plus index rows). The other "missing" plugins were the mis-filed pages above, now fixed by the renames.
• Content drift: ai_eca rewritten as a deprecation/migration notice to ai_integration_eca; ai_validations given a deprecation banner (#3552888 (closed)); call_chat_streaming corrected to reconstructChatOutput() / getNormalized(); drush.md updated with group_id and eval_provider/eval_model and the stale "test groups are coming up" line removed.
• Code-side ID bugs (stray capital in llm_media_Audio_generation, swapped llm_video_to_html/llm_video_to_image IDs) are intentionally out of scope here — a clean fix needs a hook_update_N config migration. The two video pages now carry a warning about the swapped IDs; a follow-up issue will track the code fix.

Testing instructions

1. Browse the changed Markdown pages under docs/ (or build the mkdocs site).
2. Confirm the renamed automator pages resolve, the automator index table links work, and the 3 new pages render correctly.

Checklist

• I have linked the related issue in the MR title or description
• I have performed a self-review of my own code
• I have added or updated tests, or explained in the description why this change is not covered by tests
• I have updated documentation for any new or changed functionality
• I have written testing instructions and verified them locally
• I have noted any required post-merge steps (config imports, cache rebuilds, manual changes)
• This MR contains no breaking API or hook changes, or they are explicitly documented in the description

AI Compliance

Note

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• AI Assisted Code
  Mainly written by a human; AI used for autocomplete or partial generation under full human supervision.
• AI Generated Code
  Mainly generated by AI, reviewed and approved by a human before this MR was created.
• Vibe Coded
  Generated by AI and only functionally reviewed before this MR was created.

Closes #3586542