plugin system cleanup

Summary

• fix: make plugin operations properly reenterable

• fix: type in if_not_exists

• fix: remove auto-migration flags from plugin_install & plugin_remove

• chore: don't use name Error for such a useless thing

• refactor: cleanup CaS code in plugins

• fix: remove redundant DisablePlugin governor step

• fix: cleanup backtrace logging

• chore: document why I'm not removing redundant RemovePlugin raft op

• chore: fix compilation warning

• test: reduce test_sdk_log flakiness

• fix: remove redundant UpdateTopology raft op

• fix: remove redundant EnablePlugin raft op

• refactor: extract plugin raft operations into a Op::Plugin sub operation

• fix: remove long erroneous waits when leader changes during cas operation

• refactor: use a single pico property for all plugin operations

• fix: add CallbackResult to prelude, because it's needed for all services

• fix: remove redundant read_index operations

• chore: every PropertyName must have a doc-comment

• chore: minor tweaks

• fix: used to allow removing plugins with applied UP migrations

• fix: used to leave dead _pico_plugin_migration records around

• fix: update tarantool crate to include recent fiber api fixes

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• Closes #833 (closed)
• Closes #819 (closed)
• Cherry-pick to: none
• Docs follow-up: not necessary