Introduce constructor-style HTTP assertion wrappers and alias methods; update docs and tests

[nfisher]

Motivation

• Provide a constructor-style API for HTTP assertions so actual HTTP values live in assertion structs and methods remain chainable and backward-compatible.
• Add clearer, more descriptive method names (aliases) to improve ergonomics when migrating to constructor-style and to support JSON/YAML constructor-style refactors.

Description

• Add constructor wrappers and alias methods in hammy/httpassert (Response, Request, Recorder) and implement aliases such as HasStatus, HasStatusInRange, HeaderEqualTo, HasHeader, HasHeaderContaining, BodyEqualTo, HasBodyContaining, BodyMatches, HasMethod, HasPath, URLEqualTo, HasHost, HasQueryParam, and others as thin wrappers over existing methods.
• Update request/recorder/response implementations (request.go, recorder.go, httpassert.go) to include the alias methods while preserving original behavior.
• Update the README to document the constructor-style usage and prefer the wrapper-based examples, and modify example_test.go and other tests to use the new API names.
• Adjust body-related tests to explicitly verify that request/response bodies are restored after reads instead of chaining assertions that could consume bodies, and add new unit tests verifying each alias method.

Testing

• Ran the updated unit tests for the HTTP assertion package with go test ./hammy/httpassert -v and the repository tests with go test ./..., and all tests succeeded.
• Added and executed alias-specific tests (e.g. Test_Response_HasStatus_alias_success, Test_Request_HasMethod_alias_success, Test_Recorder_BodyEqualTo_alias_success), which passed.

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Codex Task