feat(translator): implement httproutefilter host rewrite

[guydc]

What type of PR is this?

What this PR does / why we need it:

• Updates API to format requested in api: host header rewrite #4410
• Implements host rewrite based on custom header and backend dns name
• E2E and docs
• Fix Regex Path rewrite docs and translation bug

Which issue(s) this PR fixes:

Fixes #3173, #4410

[codecov]

Codecov Report

Attention: Patch coverage is 95.94595% with 6 lines in your changes missing coverage. Please review.

Project coverage is 66.05%. Comparing base (a5c3cd2) to head (b794fc4).
Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/ir/xds.go	64.70%	4 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4446      +/-   ##
==========================================
+ Coverage   66.01%   66.05%   +0.04%     
==========================================
  Files         203      203              
  Lines       31154    31238      +84     
==========================================
+ Hits        20566    20635      +69     
- Misses       9407     9417      +10     
- Partials     1181     1186       +5     

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