feat: add file complexity analyzer for review prioritization

[SimonOyaneder]

Summary

• Adds a new file analyzer module that computes complexity scores for repository files
• Includes token counting, content hashing, and parallel processing helpers
• Stores analysis results in PostgreSQL for review prioritization

Test plan

• Unit tests for complexity scoring
• Integration test with real PostgreSQL

[canon-review]

Found 4 pattern deviations: 🔴 2 high · 🟡 2 medium

[canon-review]

🟡 Naming Convention · medium · confidence: 99%

Type/interface names use snake_case instead of PascalCase.

Existing pattern: Interfaces are PascalCase (e.g., IndexProgress, RepoParams, PullRequestInfo).
Reference: src/intelligence/indexer.ts

Suggested change

	interface file_analysis_result {
	interface FileAnalysisResult {
	filePath: string;
	tokenCount: number;
	contentHash: string;
	complexityScore: number;
	}
	interface AnalysisSummary {
	totalFiles: number;
	totalTokens: number;
	highComplexityFiles: string[];
	}

[canon-review]

🔴 Duplicated Code · high · confidence: 98%

Reimplements hashing logic instead of using the shared hash utility.

Existing pattern: Hashing file/content strings is centralized via sha256Hash from src/lib/hash and reused by intelligence/github handlers.
Reference: src/intelligence/indexer.ts

Suggested change

	const compute_content_hash = (content: string): string => {
	import { sha256Hash } from "../lib/hash";
	const computeContentHash = (content: string): string => {
	return sha256Hash(content).slice(0, 16);
	};

[canon-review]

🔴 Duplicated Code · high · confidence: 97%

Adds a local concurrency mapper instead of using the shared concurrency utility.

Existing pattern: Parallel async mapping is centralized via mapWithConcurrency from src/lib/concurrency and reused in intelligence/github flows.
Reference: src/intelligence/indexer.ts

Suggested change

	const run_in_parallel = async <T, R>(
	import { mapWithConcurrency } from "../lib/concurrency";
	const results = await mapWithConcurrency(
	entries,
	5,
	async ([path, content]) => analyzeSingleFile(path, content),
	);

[canon-review]

🟡 Pattern Violation · medium · confidence: 95%

Catch variable name and rethrow pattern deviates from repository transaction pattern (error / throw error).

Existing pattern: DB transaction blocks catch error, rollback, then throw error.
Reference: CANON.md

Suggested change

	} catch (err) {
	} catch (error) {
	await client.query("ROLLBACK");
	throw error;
	}