p-token: Add custom entrypoint

[febo]

Problem

Currently p-token uses the "generic" entrypoint. There is an opportunity to give priority to most used instruction to further save CUs. Looking at token instructions from a period of one month, the most used instructions are:

Instruction	Usage (%)
transfer_checked	36.33%
transfer	13.22%
close_account	12.23%
initialize_account3	9.98%
initialize_immutable_owner	9.78%
sync_native	4.53%
initialize_account	2.58%

Other instructions account for less than 1% each.

Solution

This PR adds a custom entrypoint to p-token that includes a "fast-path" to transfer instructions. It also modifies the current processor to give priority to sync_native and initialize_immutable_owner instructions. Both modifications lead to significant improvements in CU consumption when considering the usage distribution.

| Instruction                | spl token | p-token |  p-token  |   delta   |
|                            |           |  (main) | (this PR) | (p-token) |
| -------------------------- | --------- | ------  | --------- | --------- |
| initialize_mint            |    2967   |    98   |    105    |     7     |
| initialize_account         |    4527   |   139   |    155    |    16     |
| initialize_multisig        |    2973   |   188   |    193    |     5     |
| transfer                   |    4645   |   116   |     79    |   -37     |
| approve                    |    2904   |   115   |    124    |     9     |
| revoke                     |    2677   |    95   |     99    |     4     |
| set_authority              |    3167   |   132   |    136    |     4     |
| mint_to                    |    4538   |   117   |    123    |     6     |
| burn                       |    4753   |   123   |    133    |    10     |
| close_account              |    2916   |   123   |    125    |     2     |
| freeze_account             |    4265   |   141   |    149    |     8     |
| thaw_account               |    4267   |   138   |    146    |     8     |
| transfer_checked           |    6200   |   152   |    111    |   -41     |
| approve_checked            |    4458   |   157   |    171    |    14     |
| mint_to_checked            |    4545   |   166   |    172    |     6     |
| burn_checked               |    4754   |   126   |    136    |    10     |
| initialize_account2        |    4388   |   128   |    172    |    44     |
| initialize_account3        |    4240   |   243   |    248    |     5     |
| initialize_multisig2       |    2826   |   312   |    319    |     7     |
| initialize_mint2           |    2827   |   222   |    226    |     4     |
| amount_to_ui_amount        |    2499   |   457   |    461    |     4     |
| ui_amount_to_amount        |    3161   |   690   |    694    |     4     |
| initialize_immutable_owner |    1404   |    60   |     38    |   -22     |
| sync_native                |    3045   |    88   |     62    |   -26     |

➡️ Credits to @cavemanloverboy for the "fast-path" approach.

[joncinque]

No show-stoppers from my side! I didn't calculate all of the consts myself to check, but the overall logic looks good to me.

[joncinque]

nit: let's use the consts for token account size / mint size / non-dup marker here

[febo]

We need the non-dup constant to be public in pinocchio, which will be in the next patch release. Not use whether to wait for that or make this change in a separate PR.

[febo]

@joncinque Bumped the pinocchio version, so now it is using the NON_DUP_MARKER constant.

The base branch was changed.