[BIP-912] Deprecate PoL on CoWAMM Positions

[raq0x]

Exit two CoWAMM positions held by the Balancer Treasury as outlined in https://forum.balancer.fi/t/bip-912-deprecate-pol-on-cowamm-positions-bip-666/6968.
Withdraws full BPT balance from WETH/USDC CoWAMM pool (0xf08d4dea369c456d26a3168ff0024b904f2d8b91) and WETH/BAL CoWAMM pool (0xf8f5b88328dff3d19e5f4f11a9700293ac8f638f).

These positions were originally established under BIP-666.

[github-actions]

FILENAME: BIPs/2026-W9/BIP-912-cowamm-withdraw.json
COMMIT: 97e4cf1f1bd67289bc4c0590a12fe0bc79fe86b0

Validator	Result
validate_contains_msig	✅
validate_msig_in_address_book	✅
validate_chain_specified	✅
validate_file_has_bip	✅
validate_path_has_weekly_dir	✅

[github-actions]

FILENAME: BIPs/2026-W9/BIP-912-cowamm-withdraw.json
MULTISIG: multisigs/treasury (mainnet:0x0EFcCBb9E2C09Ea29551879bd9Da32362b32fc89)
COMMIT: 97e4cf1f1bd67289bc4c0590a12fe0bc79fe86b0
CHAIN(S): mainnet
TENDERLY: 🟩 SUCCESS

+----------+----------------------------------------------------------------------------+-------+------------------------------------------------------------------------------------------------------------------+------------+----------+
| fx_name  | to                                                                         | value | inputs                                                                                                           | bip_number | tx_index |
+----------+----------------------------------------------------------------------------+-------+------------------------------------------------------------------------------------------------------------------+------------+----------+
| exitPool | 0xf08d4dea369c456d26a3168ff0024b904f2d8b91 (pools/BCoW-50WETH-50USDC-f08d) | 0     | {                                                                                                                | BIP-912    |   N/A    |
|          |                                                                            |       |   "poolAmountIn": [                                                                                              |            |          |
|          |                                                                            |       |     "raw:5194381554063539272643, 18 decimals:5194.381554063539272643, 6 decimals: 5194381554063539.272643"       |            |          |
|          |                                                                            |       |   ],                                                                                                             |            |          |
|          |                                                                            |       |   "minAmountsOut": [                                                                                             |            |          |
|          |                                                                            |       |     "raw:0, 18 decimals:0, 6 decimals: 0",                                                                       |            |          |
|          |                                                                            |       |     "raw:0, 18 decimals:0, 6 decimals: 0"                                                                        |            |          |
|          |                                                                            |       |   ]                                                                                                              |            |          |
|          |                                                                            |       | }                                                                                                                |            |          |
| exitPool | 0xf8F5B88328DFF3d19E5f4F11A9700293Ac8f638F (pools/BCoW-50BAL-50ETH-f8f5)   | 0     | {                                                                                                                | BIP-912    |   N/A    |
|          |                                                                            |       |   "poolAmountIn": [                                                                                              |            |          |
|          |                                                                            |       |     "raw:156039119661920131226849, 18 decimals:156039.119661920131226849, 6 decimals: 156039119661920131.226849" |            |          |
|          |                                                                            |       |   ],                                                                                                             |            |          |
|          |                                                                            |       |   "minAmountsOut": [                                                                                             |            |          |
|          |                                                                            |       |     "raw:0, 18 decimals:0, 6 decimals: 0",                                                                       |            |          |
|          |                                                                            |       |     "raw:0, 18 decimals:0, 6 decimals: 0"                                                                        |            |          |
|          |                                                                            |       |   ]                                                                                                              |            |          |
|          |                                                                            |       | }                                                                                                                |            |          |
+----------+----------------------------------------------------------------------------+-------+------------------------------------------------------------------------------------------------------------------+------------+----------+