Allow using HTTP config paths in the CLI

[mkysel]

Allow the CLI to load configuration via HTTP(S) or file URLs and enforce a 10 KiB read limit in config.ContractOptionsFromEnv in validation.go

This change updates config.ContractOptionsFromEnv to accept configuration paths as local filesystem paths or URLs with http, https, or file schemes, applies a 10s HTTP client timeout, enforces 2xx responses, and limits reads to 10 KiB with contextual error wrapping. It also adds net/http to imports and wraps JSON unmarshal errors with context.

• Add HTTP fetching with 10s timeout and 2xx status requirement in config.ContractOptionsFromEnv in validation.go
• Support file:// URLs with path normalization and 10 KiB read limit in config.ContractOptionsFromEnv in validation.go
• Apply 10 KiB read limit for local files and wrap errors with context in config.ContractOptionsFromEnv in validation.go
• Import net/http in validation.go

📍Where to Start

Start with config.ContractOptionsFromEnv in pkg/config/validation.go, which contains the URL/file path handling, HTTP client logic, read limits, and error wrapping.

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Macroscope summarized 27b96e7.

[graphite-app]

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