get_relative_path: shorten data_folder everywhere it appears

[abrignoni]

Follow-up to the relative-source-paths fix, prompted by @JamesHabben's question about concatenated source paths.

The gap: the decorator shortens source_path per newline segment. Artifacts that join multiple absolute paths with other separators (', ', '; ', ' ') only had the first path shortened — startswith matches the head of the concatenated string, strips one prefix, and the rest stayed absolute:

in : <data>/a.db, <data>/b.db
out: a.db, /Users/examiner/.../b.db   <- second path leaked

The fix: Context.get_relative_path now globally replaces the data_folder prefix wherever it appears, separator-agnostic — same spirit as the old file_found.replace(seeker.data_folder, '') idiom. Artifacts that already relativize before joining (Oops-style, ~24 in iLEAPP) are unaffected: relative segments pass through untouched.

Verified: unit tests cover exact path, path == data_folder, literals, already-relative, None, comma/semicolon/space-joined absolute paths, newline decorator path, and no-data_folder passthrough. pylint 10.00/10, byte-compile, PluginLoader smoke test all pass.

Affected artifacts that this transparently fixes: iLEAPP box/home_depot/idstatuscache/sysdiagnose (+skg_archive if its parts are paths), ALEAPP FCM family/siminfo/wifiConfigstore2/wifiProfiles. RLEAPP/VLEAPP have no current emitters — this keeps the four frameworks identical and future-proof.

[abrignoni]

Verification summary

Vetted this change against current main before merge. Findings:

Behavior is correct. Ran the old vs. new get_relative_path logic across 9 cases with base = /data/extract:

case	OLD	NEW
empty	''	''
exact match	''	''
normal base/a/b.txt	a/b.txt	a/b.txt
comma-join base/a.txt, base/b.txt	a.txt, /data/extract/b.txt	a.txt, b.txt
semicolon-join	a.txt; /data/extract/b.txt	a.txt; b.txt
space-join	a.txt /data/extract/b.txt	a.txt b.txt
no data_folder (passthrough)	/other/x.txt	/other/x.txt
already relative	already/relative.txt	already/relative.txt
windows sep base\a\b.txt	a\b.txt	a\b.txt

The six non-concatenation cases are byte-identical old vs. new; only the three genuinely-broken joined-path cases change, which is exactly the intent. Complements the existing per-newline shortening in the artifact_processor wrapper (which splits source_path on \n and calls this per segment) by also handling the , / ; / separators used inside a single segment.

Mechanics: current main's get_relative_path matches this PR's "before" byte-for-byte; GitHub reports MERGEABLE / CLEAN; single commit, one file, py_compile clean.

Two notes for the merger:

• The commit message says "covered by tests," but there are no test files in the repo — the table above is a manual stand-in, not automated coverage.
• The new logic uses base in full_path + .replace(...) instead of startswith + slice, so it's marginally more aggressive: a bare data_folder substring appearing as non-path content would also be stripped. In practice data_folder is an absolute extraction root that won't collide with real data, and the old startswith had the analogous /data vs /data2 prefix ambiguity, so this isn't a regression.

Touches core scripts/context.py, so leaving the merge decision to a human.