fix(okf): strip local media paths from export text

[darron]

Move local-media-path filtering into shared OKF text rendering so raw source extracts, item evidence, summaries, excerpts, and section bodies do not leak generated Local Path, local_path, or generated Local: media metadata into OKF bundles.

Previously the filter only covered X media transcript evidence. Source-level raw text and derived text could still expose machine-local media paths in exported artifacts. The export now preserves surrounding evidence while dropping only the generated local path metadata lines.

Risk: the heuristic is intentionally narrow but not schema-aware, so a user-authored line that exactly matches generated local-path metadata may also be removed.

Follow-up: keep any future generated filesystem metadata behind this shared filter, or prevent it from entering export-bound body text in the first place.

[github-actions]

PR Diff Stats

PR #50 changed 4 file(s), with +35 / -18 (53 changed lines).

Bucket	Files	Additions	Deletions	Changed
Docs	1	+2	-1	3
Tests	1	+6	-3	9
Migrations	0	+0	-0	0
Generated	0	+0	-0	0
Lockfiles	0	+0	-0	0
Config / Ops	0	+0	-0	0
Code	2	+27	-14	41
Total	4	+35	-18	53

Largest Changed Files

File	Bucket	Additions	Deletions	Changed
internal/okf/text.go	Code	+26	-0	26
internal/okf/render_item.go	Code	+1	-14	15
internal/okf/export_test.go	Tests	+6	-3	9
CHANGELOG.md	Docs	+2	-1	3

Bucket rules

• Docs: Markdown/text docs such as docs/**, README.md, and other *.md or *.txt files
• Tests: *_test.go, test/, tests/, e2e/, and JS/TS *.test.* or *.spec.* files
• Migrations: schema migration/init files such as internal/store/migrations.go and internal/store/schema_init.go
• Generated: local runtime/generated surfaces such as data/, logs/, tmp/, vault/, and web/ui/dist/
• Lockfiles: dependency lockfiles such as go.sum and package-lock.json
• Config / Ops: CI, config, packaging, skills, deploy, and scripting files such as .github/, packaging/, skills/, scripts/, Makefile, Dockerfile, Taskfile.yml, config.yaml.sample, and fly.toml
• Code: everything else