feat: rewrite as thin wrapper around supermodel CLI

Replaces the direct API client (TypeScript SDK) with the Supermodel CLI
binary. The action now installs the CLI on the runner and delegates all
analysis to `supermodel dead-code -o json`, then handles GitHub-specific
concerns (PR diff scoping, PR comment, action outputs, fail-on-dead-code).

Feature parity maintained:
- comment-on-pr, fail-on-dead-code, ignore-patterns, timeout-seconds unchanged
- PR diff scoping (scope findings to changed files) unchanged

New inputs:
- min-confidence: pass --min-confidence to CLI (high/medium/low)
- cli-version: pin the CLI version to install (default: latest)

Removed:
- @supermodeltools/sdk dependency (analysis now done by CLI)
- minimatch dependency (glob filtering now done by CLI --ignore flag)
- filterByIgnorePatterns (logic moved to CLI)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: greynewell

action.yml

@@ -23,13 +23,21 @@ inputs:
     required: false
     default: 'false'
   ignore-patterns:
-    description: 'JSON array of glob patterns to ignore'
+    description: 'JSON array of glob patterns to exclude from results (supports **)'
     required: false
     default: '[]'
+  min-confidence:
+    description: 'Minimum confidence level to report: high, medium, or low'
+    required: false
+    default: ''
   timeout-seconds:
     description: 'Maximum seconds to wait for analysis to complete (default: 7200)'
     required: false
     default: '7200'
+  cli-version:
+    description: 'Supermodel CLI version to install (default: latest)'
+    required: false
+    default: 'latest'
 
 outputs:
   dead-code-count:

dist/dead-code.d.ts

@@ -1,11 +1,29 @@
-import type { DeadCodeCandidate, DeadCodeAnalysisResponse, DeadCodeAnalysisMetadata } from '@supermodeltools/sdk';
-export type { DeadCodeCandidate, DeadCodeAnalysisResponse, DeadCodeAnalysisMetadata };
-/**
- * Filters dead code candidates by user-provided ignore patterns.
- * The API handles all analysis server-side; this is purely for
- * client-side post-filtering on file paths.
- */
-export declare function filterByIgnorePatterns(candidates: DeadCodeCandidate[], ignorePatterns: string[]): DeadCodeCandidate[];
+export type Confidence = 'high' | 'medium' | 'low';
+export type CodeType = 'function' | 'class' | 'method' | 'interface' | 'type' | 'variable' | 'constant';
+export interface DeadCodeCandidate {
+    file: string;
+    name: string;
+    line: number;
+    type: CodeType;
+    confidence: Confidence;
+    reason: string;
+}
+export interface DeadCodeMetadata {
+    totalDeclarations: number;
+    deadCodeCandidates: number;
+    aliveCode: number;
+    analysisMethod: string;
+    analysisStartTime?: string;
+    analysisEndTime?: string;
+    transitiveDeadCount?: number;
+    symbolLevelDeadCount?: number;
+}
+export interface DeadCodeResult {
+    metadata: DeadCodeMetadata;
+    deadCodeCandidates: DeadCodeCandidate[];
+    aliveCode: unknown[];
+    entryPoints: unknown[];
+}
 /**
  * Scopes dead code candidates to only files present in the changed files set.
  * Used to limit PR comments to findings relevant to the current diff.
@@ -14,4 +32,4 @@ export declare function filterByChangedFiles(candidates: DeadCodeCandidate[], ch
 /**
  * Formats dead code analysis results as a GitHub PR comment.
  */
-export declare function formatPrComment(candidates: DeadCodeCandidate[], metadata?: DeadCodeAnalysisMetadata): string;
+export declare function formatPrComment(candidates: DeadCodeCandidate[], metadata?: DeadCodeMetadata): string;