test(source/falkordb): migrate integration tests to MCP endpoint

[DylanVolz]

Description

This PR migrates the FalkorDB integration tests to use the /mcp endpoint on the MCP Toolbox Server.

Key Changes

• falkordb_mcp_test.go: Migrated legacy /api tests to /mcp

  • TestFalkorDBMCPListTools validates the full tools/list manifest for all eight FalkorDB tools configured in the test (falkordb-cypher, falkordb-execute-cypher including the read-only and graph-override variants, falkordb-schema, and falkordb-list-graphs).
  • TestFalkorDBMCPCallTool runs the same ten invocation cases as the legacy test over MCP JSON-RPC: parameterized cypher, ad-hoc execution (write stats, dry_run query plan, graph override), schema extraction on populated and nonexistent graphs, and graph listing.
  • The read-only write rejection is asserted via wantContentErr and AssertMCPError.
  • Uses t.Cleanup for server and cmd.Close cleanup.

• falkordb_integration_test.go: Extracted shared helpers so the legacy and MCP tests use the same setup and cases (no behavior change to the legacy test):

  • setupFalkorDBInstance starts the ephemeral FalkorDB container (unless FALKORDB_* points at an external instance) and restores the package-level connection variables on cleanup, so each test gets its own container.
  • getFalkorDBToolsConfig builds the shared tools file.
  • getFalkorDBInvokeTestCases holds the shared invocation cases (toolName + args map[string]any), replacing the inline requestBody JSON strings.

No shared test helpers (tests/tool.go, tests/mcp_tool.go, tests/option.go) are modified. The legacy /api FalkorDB test is kept.

Verified locally against the falkordb/falkordb:v4.18.0 testcontainer: go test -count=1 -v ./tests/falkordb/ passes (legacy REST test, MCP tools/list, and all MCP invocations).

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🛠️ Fixes #<issue_number_goes_here>

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[gemini-code-assist]

Code Review

This pull request refactors the FalkorDB integration tests by extracting setup helpers and test cases into reusable functions. It also introduces a new integration test suite in tests/falkordb/falkordb_mcp_test.go to verify the FalkorDB Model Context Protocol (MCP) server, reusing the extracted test cases to validate tool listing and invocation. There are no review comments, so I have no feedback to provide.

[AlexTalreja]

/gcbrun