Fixes #1542: Parameterize relationship query limits, add truncation flags & CLI support - #1594

Fixes #1542

Context & Solution

Issue #1542 flagged that find_callers and other relationship queries silently capped output at 20 results regardless of TOOL_RESULT_LIMITS configuration, and failed to notify callers when results were truncated.

This PR parameterizes the Cypher LIMIT clauses across relationship search queries in code_finder.py, adds truncated (bool) and result_limit (int) metadata to response envelopes, and updates CLI commands to respect configured limits.

Changes Made

• code_finder.py: Parameterized LIMIT 20 clauses with limit: Optional[int] = None across 8 relationship functions (who_calls_function, what_does_function_call, who_imports_module, find_functions_by_argument, find_functions_by_decorator, who_modifies_variable, find_function_overrides, find_function_call_chain).
• analyze_code_relationships(): Resolves TOOL_RESULT_LIMITS per query type, queries limit + 1 rows to detect truncation, slices to limit, and adds "truncated" and "result_limit" keys to output envelopes. Appends truncation notices to summary strings.
• analysis_handlers.py: Forwards "truncated" and "result_limit" flags from envelope dicts to top-level handler responses.
• cli/main.py: Updated CLI subcommands (analyze callers, analyze calls, analyze chain, analyze overrides, find decorator, find argument) to query with limit + 1 and print truncation warnings when output is capped.
• tests/unit/tools/test_relationship_tool_limits.py: Added unit tests covering limit enforcement, truncation flags, TOOL_RESULT_LIMITS env overrides, handler forwarding, and untruncated regressions.

Testing & Verification

• uv run python -m pytest tests/unit/tools/test_relationship_tool_limits.py (4/4 PASSED)
• uv run python -m pytest tests/unit/tools/ (400 PASSED, 3 SKIPPED)

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