v0.12.0

Added

• JSON output for mix ex_ast.search, mix ex_ast.replace, and mix ex_ast.diff via --format json / --json, backed by Jason.Encoder protocol implementations for ExAST result structs.
• %ExAST.CompiledPattern{} metadata for compiled patterns, including candidate signatures, structural terms, and broad/multi-node flags.
• ExAST.Pattern.compile_ast/1 for callers that need the normalized pattern AST.
• ExAST.rewrite_plan/4 and ExAST.Rewriter for inspecting replacement plans before applying patches, with overlapping-replacement conflict detection.
• File-level parallelism for unbounded ExAST.search/3 and search_many/3, configurable with :concurrency.
• Conservative source-text prefiltering using index terms to avoid parsing files that cannot match a pattern.
• ExAST.Comments.associated/3 for retrieving comments related to a source range (:before, :after, :inside, :inline, or aggregate :comment).
• Import-aware call matching for imported functions such as import Ecto.Query, only: [from: 2] matching Ecto.Query.from(_, _).
• Reach, ExSlop, and ExDNA-backed static analysis hardening in CI via an isolated tools/reach_runner project.

Changed

• ExAST.Pattern.compile/1 now returns %ExAST.CompiledPattern{} instead of a raw normalized AST. Use ExAST.Pattern.compile_ast/1 for the old AST shape.
• ExAST.search/3 results now include the matched :range.
• ExAST.replace/4 now plans rewrites before applying them and supports format: true; the CLI exposes this as --format-output.
• Syntax-aware diffing now treats same-body function renames as function updates rather than delete+insert pairs.
• mix ci now includes explicit ExSlop smell analysis and Reach smell/dead-code checks in addition to existing compile, format, Credo, Dialyzer, tests, and ExDNA checks.