feature: support aws bedrock application-inference-profile

[zeevenn]

Feature request

Currently, Avante.nvim's Bedrock provider only supports standard foundation model IDs (e.g., anthropic.claude-sonnet-4-20250514-v1:0). However, many organizations use Application Inference Profiles in Amazon Bedrock, which have ARNs in the format:

arn:aws:bedrock:{region}:{account-id}:application-inference-profile/{profile-id}

Use Case:

In our organization, IAM permissions are configured to only allow access to Application Inference Profiles, not direct foundation models. This means:

• ✅ Claude Code works with ANTHROPIC_MODEL='arn:aws:bedrock:us-west-2:xxxxx:application-inference-profile/xxxxx'
• ❌ Avante.nvim fails with 403 Forbidden when using foundation model IDs
• ❌ Avante.nvim fails with Bedrock model handler not found when using inference profile ARNs

Expected Behavior:

The Bedrock provider should accept Application Inference Profile ARNs as valid model identifiers and route requests accordingly.

Configuration Example:

{
  "yetone/avante.nvim",
  opts = {
    provider = "bedrock",
    providers = {
      bedrock = {
        model = "arn:aws:bedrock:us-west-2:xxxxx:application-inference-profile/xxxxx",
        aws_region = "us-west-2",
        aws_profile = "my-profile",
      },
    },
  },
}

References:

• Amazon Bedrock Inference Profiles

Motivation

No response

Other

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