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/073/01_gulfnews-com.txt

@@ -0,0 +1,35 @@
+Attempt to rob Dh500,000 foiled in Dubai, gang of four members arrested
+
+Defendants attacked bitcoin buyer and his friends and sprayed deodorants on their faces
+
+Robbers in Dubai tried to snatch Dh500,000 in cash from an investor who wanted to buy bitcoins. Picture for illustrative purposes only.Gulf News Archives
+
+Dubai: A group of four Dubai-based expatriates has been accused of attempted robbery of Dh500,000 from an investor in a fraudulent bitcoin transaction.
+
+According to the Dubai Court of First Instance, the four Ukrainian defendants aged between 28 and 34 years, broke into an office in the Al Barsha area of Dubai and tried to steal the cryptocurrency after attacking the investor and two of his friends.
+
+A 33-year-old Egyptian witness, who was told by the investor and another person to join them in buying the cryptocurrency, said that he went to the office carrying Dh500,000 in cash in a bag. “A man told us to wait until the arrival of the bitcoin seller. As they were getting late, the victim told the man that they would leave, when the door opened and the four Ukrainian suspects came in, attacked the victim and tried to steal the money,” said the Egyptian witness.
+
+The four defendants physically assaulted the victims and sprayed a deodorant directly on to the victims’ faces.
+
+“As the victim raised an alarm, screaming ‘thieves ... thieves’ the attackers couldn’t steal the money and they escaped from the spot,” added the Egyptian witness.
+
+Dubai Police have arrested all the four defendants who were charged with attempted robbery.
+
+Also Read: Dubai-based carpenter, who had 29 narcotic pills hidden in his stomach, sentenced to jail
+
+Also Read: Indian expat who forged boss’s signature 47 times jailed in Dubai
+
+Also Read: Sales manager in Dubai embezzled Dh788,000 from company, using fake documents
+
+Also Read: Three expats scam Dubai law firm customer
+
+The next hearing is scheduled for January 11.
+
+Man arrested in Sharjah for killing two sisters
+
+Dubai arrests singer over Dh9,000 fake visa scam
+
+Man thought he was a cat after taking drugs: Prosecutor
+
+Two fined Dh50,000 each over petrol station dispute

merge-output/staging/073/index.json

@@ -0,0 +1,16 @@
+[
+  {
+    "case": 73,
+    "n": 1,
+    "field": "url",
+    "url": "https://gulfnews.com/uae/crime/attempt-to-rob-dh500000-foiled-in-dubai-gang-of-four-members-arrested-1.76204045",
+    "host": "gulfnews.com",
+    "fetched_at": "2026-09-05T12:54:19+00:00",
+    "verdict": "FETCHED",
+    "method": "raw",
+    "http": 200,
+    "chars": 2142,
+    "sha256": "2a995827abea34c39bb196dd7a9394b7c059a34cd426887af1ab1d53ff0a8d7d",
+    "final_url": null
+  }
+]