docs: remove duplicate tool listings and improve organization

[philip]

Remove 5 duplicate tool listings, move a few tools to more appropriate sections, and update a few descriptions.

[orca-security-us]

Orca Security Scan Summary

Status	Check	Issues by priority
Passed	Infrastructure as Code	0   0   0   0	View in Orca
Passed	SAST	0   0   0   0	View in Orca
Passed	Secrets	0   0   0   0	View in Orca
Passed	Vulnerabilities	0   0   0   0	View in Orca

[Copilot]

Pull Request Overview

This PR cleans up the README documentation by removing 5 duplicate tool listings that appeared multiple times across different sections, reorganizing tools into their appropriate categories, and improving tool descriptions for clarity.

Key changes:

• Removed duplicate entries for list_organizations, list_branch_computes, list_slow_queries, explain_sql_statement, prepare_query_tuning, and complete_query_tuning
• Moved list_organizations to the Project Management section where it belongs
• Consolidated query performance tools under a single "Query Performance Optimization" section
• Updated descriptions to be more consistent and removed overly specific implementation details

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[Copilot]

[nitpick] The updated description is now too generic. While removing specific mention of Stack Auth may be intentional to be provider-agnostic, 'an Auth provider' is vague. Consider specifying 'supported Auth providers' or linking to documentation that lists compatible providers to help users understand what authentication services can be integrated.

Suggested change

	- **`provision_neon_auth`**: Provisions Neon Auth for a Neon project. It allows developers to easily set up authentication infrastructure by creating an integration with an Auth provider.
	- **`provision_neon_auth`**: Provisions Neon Auth for a Neon project. It allows developers to easily set up authentication infrastructure by creating an integration with a supported Auth provider. See [Supported Auth Providers](https://docs.neon.tech/auth/providers) for a list of compatible authentication services.

[claude]

Code Review Summary\n\nPR: #125 - docs: remove duplicate tool listings and improve organization\nReviewer: Claude Code\nCommit: db940dd\n\n---\n\n### Review Statistics\n- Files Changed: 1 (README.md)\n- Lines Added: +7\n- Lines Removed: -18\n- Issues Found: 0\n\n### Severity Breakdown\n- 🔴 Critical: 0\n- 🟡 Important: 0\n- 🔵 Consider: 0\n\n---\n\n### Assessment\n\nThis is a documentation-only PR with no code changes. After thorough review, no significant issues were found.\n\n### What This PR Does Well ✅\n\n1. Removes Confusion: Eliminated 5 duplicate tool listings that could confuse users\n2. Improved Organization: Moved list_organizations from Branch Management to Project Management (more logical placement)\n3. Better Categorization: Consolidated duplicate sections ("Compute Management" and "Query Performance Tuning" were redundant)\n4. Clearer Descriptions: Minor wording improvements for provision_neon_auth and query tuning tools\n5. Accuracy: Added "last active time" detail to list_branch_computes description\n\n### Changes Summary\n\nRemoved Duplicates:\n- list_branch_computes (was listed twice)\n- list_slow_queries (was listed twice)\n- "Compute Management" section (duplicate of Branch Management content)\n- "Query Performance Tuning" section (duplicate of Query Performance Optimization)\n\nReorganized:\n- Moved list_organizations to Project Management section (better fit)\n\nDescription Updates:\n- provision_neon_auth: Changed from specific "Stack Auth" to generic "Auth provider"\n- list_branch_computes: Added "last active time" to feature list\n- Query tuning tools: Minor wording polish\n\n---\n\n### Recommendation\n\n✅ APPROVE - This PR improves documentation quality with no risks. Ready to merge.\n\n---\n\nNote: Automated checks (lint, build, formatting) are handled by CI pipeline.