Context

We restore the all or nothing semantics for manager operation batches by ensuring that failing Reveal operations don't take effect (cf. #2386 (closed)). We revert changes introduced by !587 (merged) (cf #338 (closed)).
For this, we refactor apply_operation so that the effect of revealing the manager is implemented by apply_external_manager_operation_content instead of by precheck_manager_contents.
We enforce a new structural condition on manager operations batches, expecting that Reveal operations are placed only at the head of the batch - a new Permanent error, Incorrect_reveal_position (see #2774 (closed)).
This simplifies the work of the %(OKR 2022Q3 - 1.1) Pipelining project: the precondidition of Reveal becomes disentangled from its effect, easing the process of splitting pure preconditions (validate), from effects (apply proper).
In order to better test Reveal operations in Protocol integration tests, we extend the signature of manager_operation and other derived helpers to disable attaching a Reveal operations - the current behaviour is preserved, by enabling ?force_reval by default.
In the process of writing and rewriting tests, we inverted the ?expect_failure and ?expect_apply_failuree optional handles for add_operation in Incremental mode helpers, as they implemented opposite semantics (cf. !4877 (6e40ebc6)).

Manually testing the MR

We have added several (~10) integration tests for the Reveal operation under (../test/integration/operation.ml), addressing the issues highlighted by #2386 (closed) and #2774 (closed).
The commit history of the MR is written to start with the work extending proto test helpers, including the swap of ?expect_failure and ?expect_apply_failure, so manually testing that some of the new integration tests (e.g. test_no_reveal_when_gas_exhausted ) break on Alpha before the changes included in this MR requires a bit of work on the history.
A few existing Operation integration tests were updated to better assert the new semantics, including reporting a new Branch error Empty_implicit_contract, when an account becomes empty in the middle of a batch (cf. !4877 (6e40ebc6))
We update previous tezts (#2774 (closed)) to show unified errors for repeated reveals in batches -- for protocols > Jakarta.

Document the interface of any function added or modified (see the coding guidelines)
~~[ ] Document any change to the user interface, including configuration parameters (see node configuration)~~
Provide automatic testing (see the testing guide).
For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
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Update related tezos Stack exchange question to reflect fixes.
#3111 (closed) to improve the documentation of the application results for (batches) of manager operations in the Docs.
#3078 (closed) remove the optional argument from Reveal_manager.
#2979 (closed) make ?force_reveal to default to false and adapt integration tests.
Advertise breaking changes in proto integration test suite w/ DevTeam/ProtoProposal channels.
#3143 (closed) Refactor must_be_allcoated to take a pkh source argument instead.
#3144 (closed) re-unify the errors raised with get_manager_key.

Edited Jun 03, 2022 by Germán Delbianco