Refactor bdk-cli structure

[tvpeter]

Description

This PR restructures the bdk-cli codebase to move away from a monolithic handling model towards a modular architecture. The primary goal is to improve code readability, simplify the addition of new features, and decouple core logic into smaller modules.

Notes to the reviewers

To achieve the above-stated goal, maximum effort was made to prevent introducing new bugs. As a result, the existing execution logic was preserved as much as possible.

This PR introduces two new subdirectories under src:

• handlers: This contains all the subcommands' execution logic grouped logically according to the top-level commands. Modules include the config, descriptor, key, offline, online and repl modules. They each contain structures for the subcommand, execution logic, and implementation of the top-level enum.
• utils: This subdirectory contains helper functions used across the app. They are also grouped logically according to related functionality. So far, we have the descriptor-related module, the output that formats responses, and the types module that defines response structures.

Other notable changes:

• main module is retained with added functionality of routing requests to the right module for execution.
• All client-related functionalities have been moved from various modules into the client module, and it defines the enum that holds all the available clients, as well as impl the functionalities such as broadcasting transactions and syncing operations.
• The AppCommand trait that defines how each subcommand should be structured and the execute method they should implement.
• The AppContext struct that holds the universal parameters that subcommands may need. Each subcommand's execute method accept this struct and use the params for its execution.
• The output module in the util subdirectory attempts to present a uniform presentation layer by having an output trait, the FormatOutput trait, which is implemented by all types presenting data response to the user.
• Collapsed the wallet subdirectory into the persister module that defines all structures and functionalities related to persistence.

Changelog notice

• In the key derive subcommand, when printing help message, the clap arg for env=“PATH” often pull all system and displays all system paths. This has been changed to derivation_path I.e. env=“DERIVATION_PATH” to prevent clap from picking the system paths and rendering it
• Moved the wallet subdirectory that served as persister into the persister module
• Moved DatabaseType enum from commands module into persister module
• Removed the —pretty flag

Checklists

All Submissions:

• I've signed all my commits
• I followed the contribution guidelines
• I ran cargo fmt and cargo clippy before committing

[codecov]

Codecov Report

❌ Patch coverage is 5.06415% with 1406 lines in your changes missing coverage. Please review.
✅ Project coverage is 8.35%. Comparing base (7c33b33) to head (70965f0).
⚠️ Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
src/handlers/types.rs	6.34%	236 Missing ⚠️
src/handlers/offline.rs	0.00%	221 Missing ⚠️
src/handlers/online.rs	0.00%	191 Missing ⚠️
src/utils/descriptors.rs	0.00%	138 Missing ⚠️
src/utils/common.rs	0.00%	134 Missing ⚠️
src/handlers/mod.rs	7.04%	132 Missing ⚠️
src/handlers/config.rs	0.00%	83 Missing ⚠️
src/backend/mod.rs	0.00%	77 Missing ⚠️
src/handlers/repl.rs	0.00%	61 Missing ⚠️
src/handlers/descriptor.rs	0.00%	54 Missing ⚠️
... and 4 more

Additional details and impacted files

@@            Coverage Diff            @@
##           master    #278      +/-   ##
=========================================
- Coverage   10.96%   8.35%   -2.62%     
=========================================
  Files           8      20      +12     
  Lines        2526    2383     -143     
=========================================
- Hits          277     199      -78     
+ Misses       2249    2184      -65     

Flag	Coverage Δ
rust	8.35% <5.06%> (-2.62%)	⬇️

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[notmandatory]

concept ACK, this is a big change might be a good idea to do a live walk through some time on discord to help with the review process.

[tvpeter]

concept ACK, this is a big change might be a good idea to do a live walk through some time on discord to help with the review process.

Alright, anytime we are chanced.

Also, I would want most of the PRs to get in before this one because it will be challenging for others to rebase and fix conflicts.