chore(context7): expand context7.json with full schema metadata and agent rules

[jesseoue]

Summary

Expand context7.json from a two-field placeholder (url, public_key) into the full documented Context7 configuration schema so that every coding agent pulling LeadMagic docs through Context7 (Cursor, Claude, ChatGPT, Windsurf, Cline, etc.) receives deterministic, on-brand context and inherits the same guard rails that already live in SECURITY.md and README.md.

The existing claim is preserved — the public_key field is retained, so the admin-panel invite / multi-version management we set up on Context7 continues to work.

What changed

context7.json

Field	Before	After
$schema	—	https://context7.com/schema/context7.json (enables VS Code / Cursor autocomplete + validation)
projectTitle	—	LeadMagic API
description	—	Platform-neutral blurb mirroring the repo description and leadmagic.io positioning
branch	—	main (explicit, not inferred)
folders	—	[] (scan full repo; root markdown is always included)
excludeFolders	—	node_modules, dist, build, coverage, .github
excludeFiles	—	package-lock.json, CHANGELOG.md, LICENSE
rules	—	6 rules (see below)
url	kept	kept
public_key	kept	kept

Agent rules (the "hashtags" reviewers will care about most)

These are embedded directly in the doc context returned to coding agents, so they can't miss them:

1. Platform-neutral language. No claims that LeadMagic scrapes or indexes a specific social network — matches profile/README.md, SECURITY.md, and the leadmagic.io copy.
2. REST auth. Base URL https://api.leadmagic.io, X-API-Key header, key hygiene reminder (no client-side embedding, keys issued from app.leadmagic.io).
3. Hosted MCP. Points at https://mcp.leadmagic.io/mcp, calls out the 10-tool surface, and enumerates all three supported auth modes: OAuth 2.1 (Authorization Code + PKCE, S256) with DCR, the documented static public client (client_id 4b9eLjoGVCJ1Dvnc, no secret), x-leadmagic-key API-key auth, or Authorization: Bearer <token>.
4. Canonical OpenAPI. Points coding agents at leadmagic-openapi-3.1.yaml / .json at the repo root and prefers YAML for snippets.
5. Don't invent endpoints or credit costs. Defers to README.md for the authoritative credit-cost table and route mapping — prevents hallucinated pricing.
6. Installer allow-list. Reinforces the brand-impersonation guidance in SECURITY.md: npm/pip packages named leadmagic* published by third parties are not endorsed.

Why now

The placeholder context7.json worked for claiming the library but left all downstream retrieval at the mercy of LLM inference. After the hosted MCP sign-in rollout (PR #7) and the org profile rewrite (LeadMagic/.github#2), Context7 is now the primary path by which AI coding assistants discover LeadMagic auth, MCP client setup, and brand guidance. Making the guard rails retrieval-native closes the loop.

Risk / blast radius

• Schema-only change. No code, no OpenAPI changes, no CI touch, no runtime impact.
• Context7 re-parses on merge. Next resolve-library-id / get-library-docs call for leadmagic/leadmagic-openapi picks up the new title, description, and rules automatically.
• Claim preserved. public_key retained; admin panel access continues to work.
• Valid JSON (validated locally with python3 -c 'import json; json.load(...)').

Follow-up (not in this PR)

Repo topics on GitHub will be refreshed in a separate settings-only change (tightening to the tags below) so this PR stays strictly file-based and reviewable in GitHub's diff viewer:

• Add: b2b-data, contact-enrichment, mcp-server, llms-txt
• Remove: schema (redundant with openapi / openapi-3)

Test plan

• python3 -c "import json; json.load(open('context7.json'))" — valid JSON.
• Verified required / optional fields against Context7's adding-libraries docs.
• public_key retained — existing claim intact.
• $schema URL matches the documented value (enables editor autocomplete).
• Post-merge: confirm Context7 re-parses the repo and the admin panel shows the new projectTitle / description.
• Post-merge: spot-check a retrieval via resolve-library-id + get-library-docs and confirm one of the rules appears in the returned context.