Accept absent map-level sourcesContent and preserve null source-name slots alongside known originals and aligned content. Represent unnamed local declarations explicitly, retain leaf-local and flattened indices, and preserve declared indexed-section order across consumers.
Account for added indices before browser output allocation. Accept legacy retained rows without indices. Consolidate public CLI/MCP source-map fixtures and update the stale named-source-only assertion.
BREAKING CHANGE: Browser source-map original and mapping rows expose null for unavailable source names instead of inventing an unknown-source string. New index fields are optional when reading older retained evidence.
Refs #2023, #2024
Pass typed map objects into the codec and reuse validated TraceMap instances for regular and indexed lookups. Remove whole-map serialization, duplicate leaf decoding, an array-copy wrapper, and the unused offset-validation mode in artifact declaration collection.
Validation: source-map and browser consumer suites (126 tests), declaration tests, and artifact reconstruction boundaries pass. Section overlap checks and raw source declarations remain intact.
Move the indexed sections walk shared by the browser fetcher and
the artifact reader into domain/sourceMapEnvelope with the
fetchers stricter offset validation as an option; both validators
keep their leaf strictness. Rename the browser CDP stringValue to
cdpStringValue across its 18 files, fold the fingerprint duplicate
into the static helper, and rename the version-keys shadow to
nonEmptyString.