fix(examples): add bonding_curve_v2 to learning examples (#160)

* fix(examples): add bonding_curve_v2 remaining account to learning examples

Add the required bonding_curve_v2 PDA as a remaining account to buy/sell
instructions in manual_buy, manual_sell, mint_and_buy, and mint_and_buy_v2
learning examples, matching the pump.fun program upgrade.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix(examples): add bonding_curve_v2 to manual_buy_geyser and manual_buy_cu_optimized

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

learning-examples/manual_sell.py

@@ -147,6 +147,14 @@ def _find_fee_config() -> Pubkey:
     return derived_address
 
 
+def _find_bonding_curve_v2(mint: Pubkey) -> Pubkey:
+    derived_address, _ = Pubkey.find_program_address(
+        [b"bonding-curve-v2", bytes(mint)],
+        PUMP_PROGRAM,
+    )
+    return derived_address
+
+
 async def get_fee_recipient(
     client: AsyncClient, curve_state: BondingCurveState
 ) -> Pubkey:
@@ -312,6 +320,12 @@ async def sell_token(
                 is_signer=False,
                 is_writable=False,
             ),
+            # Remaining account: bonding_curve_v2 (readonly, required for all coins)
+            AccountMeta(
+                pubkey=_find_bonding_curve_v2(mint),
+                is_signer=False,
+                is_writable=False,
+            ),
         ]
 
         discriminator = struct.pack("<Q", 12502976635542562355)