docs(llm-analytics): add Claude Code installation guide

[andrewm4894]

Summary

• Adds a new LLM analytics installation guide for sending Claude Code sessions to PostHog
• Covers setup via the PostHog AI plugin (claude plugin install posthog), which uses a SessionEnd hook to automatically capture generations, tool executions, and traces
• Includes configuration options (env vars, privacy mode, trace grouping), verification steps, and retroactive ingestion of past sessions
• Adds Claude Code to the sidebar navigation in the LLM analytics installation section

Assumes PostHog/ai-plugin#24 has been merged.

Test plan

• Verify the new page renders correctly at /docs/llm-analytics/installation/claude-code
• Verify Claude Code appears in the installation platform grid with the Anthropic icon
• Verify sidebar navigation shows Claude Code between Pi Coding Agent and Manual capture
• Verify all internal links in the guide resolve correctly

https://claude.ai/code/session_015Y4J4R4GUpWx595wwgCsfb

[github-actions]

Deploy preview

Status	Details	Updated (UTC)
🟢 Ready	View preview	Apr 13, 2026 08:44AM

[github-actions]

Vale prose linter → found 10 errors, 6 warnings, 0 suggestions in your markdown

Full report → Copy the linter results into an LLM to batch-fix issues.

Linter being weird? Update the rules!

contents/docs/llm-analytics/installation/claude-code.mdx — 10 errors, 6 warnings, 0 suggestions

Line	Severity	Message	Rule
39:279	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
39:322	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
43:37	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
44:21	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
45:20	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
46:17	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
53:61	warning	Use 'project token' instead of 'project API key'. The project token (phc_) is not an API key.	PostHogBase.ProjectToken
63:70	warning	Capitalize 'Logs' for PostHog's product. Use 'logs' for the general industry concept.	PostHogBase.ProductNames
67:45	warning	Use 'project token' instead of 'project API key'. The project token (phc_) is not an API key.	PostHogBase.ProjectToken
122:51	warning	Use 'project token' instead of 'project API key'. The project token (phc_) is not an API key.	PostHogBase.ProjectToken
137:196	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
151:24	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
152:18	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
152:176	warning	Use descriptive link text instead of '[learn more]'.	PostHogBase.DescriptiveLinkText
153:19	error	Hi, Andy here... use an en dash ( – ) with spaces. On Mac, holding down the Option and hyphen key will give you an en dash.	PostHogBase.EnDash
153:123	warning	Use descriptive link text instead of '[learn more]'.	PostHogBase.DescriptiveLinkText