--podman-build-args breaks CLI argument precedence over compose.yaml

[DoctorD90]

Describe the bug

Build arguments defined inside the --podman-build-args flag do not maintain proper CLI precedence over build arguments defined in compose.yaml. The parameters passed via --podman-build-args are appended before the ones evaluated from compose.yaml, causing the compose.yaml values to override the CLI values (since the last flag wins in Podman/Docker CLI evaluation).

To Reproduce
Steps to reproduce the behavior:

1. Define a compose.yaml with a build argument set to 0:

services:
  app:
    build:
      context: .
      args:
        CUSTOM_VAR: 0

2. Run podman-compose overriding the argument via --podman-build-args:
   podman-compose --podman-build-args="--build-arg CUSTOM_VAR=1" build

3. Observe the underlying podman build command generated and executed by podman-compose:
   podman build --build-arg CUSTOM_VAR=1 --build-arg CUSTOM_VAR=0 .
   Here, CUSTOM_VAR=1 (from CLI) is litterally placed before CUSTOM_VAR=0 (from compose.yaml) without being evaluated. As a result, CUSTOM_VAR=0 overrides CUSTOM_VAR=1, effectively violating the expected CLI > compose.yaml precedence.

4. Run podman-compose using the argument --build-arg:
   podman-compose build --build-arg CUSTOM_VAR=1

5. The output is correctly evaluated:
   podman build --build-arg CUSTOM_VAR=1 .

Expected behavior
The precedence hierarchy for build arguments should consistently be:

• CLI Flags (Highest priority)
• compose.yaml / docker-compose.yml
• Dockerfile / Containerfile (Lowest priority)

Any --build-arg supplied via the CLI (whether passed directly or encapsulated via --podman-build-args) should take precedence over values defined inside the compose.yaml file.

Actual behavior
When passing a build argument using --podman-build-args="--build-arg VAR=val", podman-compose injects the flag early into the generated podman build command. It then appends the arguments parsed from compose.yaml after it.

Since Podman evaluates multiple --build-arg declarations sequentially and applies the last one, the value from compose.yaml wins over the CLI value provided inside --podman-build-args.

MAYBE this probably affects also other evaluation topics like the one reported here: #1174