Fix broken documentation links in troubleshooting README

Co-authored-by: realcodywburns <13103499+realcodywburns@users.noreply.github.com>

Author: Copilot

docs/images/fukuii-logo-cute.png

@@ -0,0 +1,23 @@
+# Investigation Reports
+
+This directory contains detailed historical investigations of issues encountered during Fukuii development and operations. These reports document root cause analysis, debugging processes, and resolutions.
+
+## Available Reports
+
+- **[Contract Test Failure Analysis](CONTRACT_TEST_FAILURE_ANALYSIS.md)** — Investigation of gas calculation discrepancies in contract tests (✅ Resolved - test fixture data issue)
+- **[FastSync Timeout Investigation](FASTSYNC_TIMEOUT_INVESTIGATION.md)** — Analysis of blockchain fast synchronization timeout scenarios
+- **[Integration Test Classification](INTEGRATION_TEST_CLASSIFICATION.md)** — Categorization and analysis of integration test failures
+
+## Purpose
+
+These investigation reports serve as:
+- Historical record of significant issues and their resolutions
+- Reference material for similar future issues
+- Documentation of debugging methodologies and approaches
+- Knowledge base for the development team
+
+## Related Documentation
+
+- [Troubleshooting Guides](../troubleshooting/README.md) — Step-by-step solutions for common scenarios
+- [Known Issues & Solutions](../runbooks/known-issues.md) — Current known issues with workarounds
+- [Operations Runbooks](../runbooks/README.md) — Operational procedures and guides

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@@ -12,16 +12,16 @@ Welcome to the Fukuii troubleshooting guides! This directory contains step-by-st
 
 ## Quick Links
 
-- [Operations Runbooks](../runbooks/) — Day-to-day operational guides
+- [Operations Runbooks](../runbooks/README.md) — Day-to-day operational guides
 - [Known Issues & Solutions](../runbooks/known-issues.md) — Common scenarios with solutions
 - [Log Analysis](../runbooks/log-triage.md) — Understanding log messages
-- [Investigation Reports](../investigation/) — Historical issue investigations
+- [Investigation Reports](../investigation/README.md) — Historical issue investigations
 
 ## Getting Help
 
 If you can't find what you're looking for:
 
 1. Check the [Known Issues](../runbooks/known-issues.md) list
-2. Review relevant [Investigation Reports](../investigation/)
+2. Review relevant [Investigation Reports](../investigation/README.md)
 3. Search [GitHub Issues](https://github.com/chippr-robotics/fukuii/issues)
 4. Open a new issue with detailed information — we're happy to help!