task: #3621876 Restructure the Views Agent system prompt and remove list_sample_view

Closes #3621876

Summary

Restructures the shipped Views Agent's system_prompt with explicit sections - Safety Rules, Key Concepts, Handler Types, and Option Value Formats - so the model has concrete, verified JSON shapes for every display_option/handler it can set (pager, access, cache, style/row, CSS class, "more" link, boolean/bundle filters, sort order) instead of having to infer them. Adds per-workflow sections and worked Common Workflow examples (content listing page, adding fields, exposed filters, a block display, pager/access/cache/style, CSS class and "more" link).

Also removes ai_agents_views:list_sample_view from the agent's tool set (the plugin itself is untouched, just no longer part of this agent), and drops the stray uuid and the no-longer-applicable node module dependency from the shipped config.

Changes

• config/install/ai_agents.ai_agent.views_agent.yml: rewritten system_prompt; list_sample_view removed from tools, tool_settings, and tool_usage_limits; uuid and the node dependency removed.
• tests/src/Kernel/Integration/ViewsAgentTest.php: removed the step that exercised ai_agents_views:list_sample_view as its own tool, and renumbered the step after it. testAgentToolsResolve() needed no change - it iterates $agent->get('tools') dynamically rather than asserting specific tool IDs.

Test plan

• Full kernel + integration suite for ai_agents_views passes with this change: 62/62 tests, 614 assertions, no failures (1 pre-existing unrelated skip).
• Every worked example in the new Option Value Formats section was verified against the real update_view_plugins/ create_view_handler tools before being written into the prompt, not assumed.

Closes #3621876

AI-Generated: Yes (Used Claude Code to draft and verify the worked examples for the Views Agent's prompt against the real tools, restructure the prompt, remove the list_sample_view tool reference, and update the integration test.)