Small misc fixes

[brentstone]

Describe your changes

• Closes namadac query-protocol-parameters shows tx_allowlist instead of vp_allowlist #3927
• uses max_block_gas = 15_000_000 in testing
• fixes an UnbondError variant message
• Query latest PoS inflation rate in addition to staking rewards rate

Checklist before merging

• If this PR has some consensus breaking changes, I added the corresponding breaking:: labels
  • This will require 2 reviewers to approve the changes
• If this PR requires changes to the docs or specs, a corresponding PR is opened in the namada-docs repo
  • Relevant PR if applies:
• If this PR affects services such as namada-indexer or namada-masp-indexer, a corresponding PR is opened in that repo
  • Relevant PR if applies:

[codecov]

Codecov Report

Attention: Patch coverage is 91.66667% with 1 line in your changes missing coverage. Please review.

Project coverage is 74.02%. Comparing base (c465b7d) to head (99a4dc9).
Report is 28 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/sdk/src/rpc.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3940      +/-   ##
==========================================
- Coverage   74.02%   74.02%   -0.01%     
==========================================
  Files         341      341              
  Lines      106560   106567       +7     
==========================================
+ Hits        78879    78884       +5     
- Misses      27681    27683       +2     

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