Configuration management for Still snapshot testing.

Supports configuration from:
- deps.edn / bb.edn / project.clj (:still/config key)
- deps.edn aliases (:still/config in :aliases map)
- Runtime overrides via still.config/override!
- Environment variables (for CI/CD)

Alias-specific configuration in deps.edn is detected automatically from:
- clojure.basis system property (when using tools.deps)
- STILL_ALIASES environment variable (comma-separated)

All configuration keys accept both British and American spellings
(e.g., :colour? or :color?, :serialisers or :serializers).

Core snapshot testing API for Still.

Provides two main functions:
- snap: Filesystem-based snapshot testing with dual behaviour (test vs REPL)
- snap!: Inline snapshot testing with automatic source code editing

Diff visualisation for snapshot mismatches.

Provides colourised, structured diffs using lambdaisland/deep-diff2.

Source code location tracking for snap! calls.

Captures file path, line, and column information from the call site to enable
automatic source editing.

Node.js filesystem utilities for snap! source editing.

Source code rewriting for snap! inline snapshots.

Uses rewrite-clj to parse, locate, and modify snap! calls in source files
while preserving formatting and comments.

Source code rewriting for snap! inline snapshots in ClojureScript.

Uses rewrite-clj (which supports ClojureScript) for AST manipulation
and still.node-io for Node.js file I/O.

Custom serialisation for snapshot values.

Provides a protocol-based system for custom type serialisation, with built-in
handlers for common edge cases like timestamps, UUIDs, and unstable values.

Snapshot file management.

Handles reading, writing, and organising snapshot files on disk (or alternative
storage for ClojureScript).

Snapshot management utilities for bulk updates, pruning, and review.

Provides CLI-friendly operations for managing snapshots.