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/039/01_cointelegraph-com.txt

@@ -0,0 +1,25 @@
+Two Bogus Bitcoin Brokers Charged With $365,000 Cash Robbery In Singapore
+
+Written by Marie Huilletformer writerReviewed by Igor Belkinformer editor
+
+Two sham Bitcoin sellers have been charged with assault and the alleged theft of $365,000 cash from a Malaysian man in Singapore.
+
+Two 36-year-old men have been arrested in Singapore after allegedly stealing $365,000 in cash from a Malaysian man who wanted to buy Bitcoin (BTC) from them, local media outlets reported Thursday, April 12.
+
+The victim, Pang Joon Hau, had come to Singapore expressly to buy Bitcoins with cash, and believed both men to be Bitcoin sellers, arranging to meet them in his hotel on April 8.
+
+The two men are said to have assaulted both Mr. Pang and his broker, fleeing with the cash.
+
+One of the accused, Mohd Abdul Rahman Mohama, allegedly claimed he was a part-time Bitcoin broker. He is reported to have given his accomplice Syed Mokhtar Syed Yusope about $10,000 and himself spent around $80,000 on luxury goods, including a Rolex watch worth $45,800. The remaining $271,000 are yet to be accounted for. The two were arrested April 9th and 10th, respectively.
+
+At a press conference April 12, Singapore Commander of Central Police Division, Assistant Commissioner of Police Arthur Law said that it is “highly unusual” for people to transact Bitcoin in person, and that Singaporean police are now investigating the origins of Mr. Pang’s large sum of cash.
+
+In January 2018, St. Petersburg crypto blogger Pavel Nyashin was robbed of 24 mln rubles in cash from a safe in his home, after “boasting” of his crypto-derived wealth online.
+
+Cointelegraph is committed to independent, transparent journalism. This news article is produced in accordance with Cointelegraph’s Editorial Policy and aims to provide accurate and timely information. Readers are encouraged to verify information independently.
+
+Bitcoin ETF inflows hit $3.8B in strongest three-week stretch of 2026
+
+Bitcoin ETF inflows hit $731M, highest since January as BTC reclaims $80K
+
+Bitcoin reclaims $80K as DXY falls amid continuing suspected yen intervention

merge-output/staging/039/index.json

@@ -0,0 +1,16 @@
+[
+  {
+    "case": 39,
+    "n": 1,
+    "field": "url",
+    "url": "https://cointelegraph.com/news/two-bogus-bitcoin-brokers-charged-with-365000-cash-robbery-in-singapore",
+    "host": "cointelegraph.com",
+    "fetched_at": "2026-09-05T12:55:53+00:00",
+    "verdict": "FETCHED",
+    "method": "raw",
+    "http": 200,
+    "chars": 2100,
+    "sha256": "8653a4bbdf6e5f2938d3d8568127c04cd9b442604e67a78d871fd3a3959b80e5",
+    "final_url": null
+  }
+]