feat(sources): fetch linked URLs for the 252 spreadsheet-only cases

Until now only cases 357+ (plus a few older ones) had their linked URLs
fetched; the other 252 dossiers held just the text pasted into the
spreadsheet, often only the lede. This pass fetches every linked URL for
those cases so the full text is on file before link rot takes it.

- stage_all.py: new --include-sheet-cases flag that lifts the skip on
  cases holding spreadsheet articles. Resumable as before.
- staging/: raw extracts and index.json for the 252 cases.
- sourced-articles.json, case-files-manifest.json: 188 new UNTRIMMED
  blocks. 179 cases gained at least one fetched article; 73 got none
  (49 BLOCKED, 18 THIN, 9 DEAD, 4 video/social, 3 ERROR).
- sources/*.txt: rebuilt with build_cases.py --all. Sheet pastes are
  kept; fetched blocks sit beside them under the NOT YET TRIMMED banner.
  Files previously committed with CRLF are now LF.
- wayback-availability.json: Wayback snapshots exist for 73 of the 98
  failed URL slots; input for an archive-fetch pass.
- README-START-HERE.md: progress note and next step.

verify_all.py PASSES (1836 checks).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GZZENdTLzNGsbNy4DyF1yt

merge-output/staging/038/01_fox4news-com.txt

@@ -0,0 +1,21 @@
+Bitcoin bandits target Dallas County cryptocurrency ATMs | FOX 4 Dallas-Fort Worth
+
+Dallas is a startup for bitcoin ATMs where the cryptocurrency can be bought with cash or exchanged for cash.
+
+In late March, two bitcoin ATMs were ravaged by robbers who used high-powered pepper spray known as bear spray to overpower clerks and rob the machines.
+
+Bitcoin is still relatively new and has only been around for about a decade. The new technology has created new thievery. Police in Irving and Mesquite are now looking for the bitcoin bandits.
+
+A bitcoin ATM at a Mesquite gas station was targeted on March 28. Video shows a man buying Gatorade at while at the counter who looks right at the camera. He then returns and sprays the female clerk with bear spray. His partner then breaks in the bitcoin ATM.
+
+“Seems like these machines do contain some cash,” explained Mesquite Police Lt. Brian Parrish. “Apparently, there comes a point when you exchange bitcoins for cash.”
+
+Irving saw the first bitcoin robbery on March 22.
+
+“Once the suspects incapacitated the clerk, then they were able to just break into it and steal the cash cassettes,” explained Irving Police Officer James McLellan.
+
+The motive is the same in both bitcoin robberies. In the Irving case, a heavyset guy in a gray hoodie goes in and sprays the clerk. A thin man in a Raiders hat then hands him a crowbar and goes to work on the ATM machine.
+
+“It’s one thing to steal or rob from someone,” Parrish said. “It’s another to hurt a defenseless clerk.”
+
+Crime Stoppers is offering $5,000 for the names of the bitcoin bandits. Anyone with information is urged to contact Mesquite or Irving PD.

merge-output/staging/038/index.json

@@ -0,0 +1,16 @@
+[
+  {
+    "case": 38,
+    "n": 1,
+    "field": "url",
+    "url": "https://www.fox4news.com/news/bitcoin-bandits-target-dallas-county-cryptocurrency-atms",
+    "host": "fox4news.com",
+    "fetched_at": "2026-09-05T12:55:55+00:00",
+    "verdict": "FETCHED",
+    "method": "raw",
+    "http": 200,
+    "chars": 1654,
+    "sha256": "4bb57c37fbef9162cedd0ac3827ac68f56e09b16f9db08c93bc9135b118868e4",
+    "final_url": null
+  }
+]