Add a `CreatePriceObservations` instruction that registers a TWAP
price-observations account for a pool over a time window, via a chained
call to the configured TWAP oracle program. The pool acts as the price
source: the AMM authorizes it with its pool PDA seed so the oracle ties
the feed to that pool.
The feed's initial tick is read from the pool's authoritative
`CurrentTickAccount` (validated against its pool-derived PDA) rather than
being supplied by the caller, so the feed cannot be seeded at a forged
price — mirroring what `RecordTick` does. The clock is verified to be the
canonical 1-block LEZ clock, and creation is rejected if the observations
account already exists.
To support the chained call, `AmmConfig` and the `Initialize` instruction
are extended with a `twap_oracle_program_id` that the instruction reads.
Add an admin authority to the AMM config so configuration can be changed
after initialization. AmmConfig gains an `authority` field, set by
Initialize, and a new UpdateConfig instruction lets that admin change
config values.
UpdateConfig is access-controlled: the authority account must equal the
stored config.authority and be passed authorized (signed). Both fields are
optional — token_program_id updates the chained-call token program, and
new_authority transfers admin control to a different account. Without this
gate any caller could repoint the AMM at a malicious token program.
r4bbit