Add a Bold() helper to the console package that applies bold
formatting when color is enabled. Use it to highlight key dynamic
values (image names, paths, URLs, hostnames) in user-facing
messages so they stand out within the dim-prefixed lines.

Also remove single quotes around values where bold makes them
visually distinct without needing quoting.

Move 'Generating model schema...', 'Using local coglet wheel...',
and 'Using local cog wheel...' from info to debug level. These are
implementation details that clutter normal output but remain visible
with --debug.

Add blank lines after 'Building Docker image...' (before Docker
build output) and after 'Running prediction/training...' (before
model output) to visually separate Cog's framework messages from
external output.

Introduce a Style type that controls the icon/color of a log line
independently from the log level. This allows Success to display at
info level (same filtering) but with a green ✓ prefix.

New styles can be added by extending the Style enum without touching
the level hierarchy.

Apply Success to: image built, cog init completion, login success,
and image pushed messages. Drop the ✅ emoji from init since the
green ✓ prefix replaces it.

Add InfoUnformatted/InfoUnformattedf methods that write to stderr at
info level without any icon prefix. These are used for conversational
and interactive output (login prompts, instructions) where the gear
prefix would be visual noise.

Long lines are wrapped to terminal width when stderr is a TTY, same
as prefixed output.

Apply to login flows in both Replicate and generic providers: replace
console.Info with console.InfoUnformatted for all user-facing prompts
and instructions. Rename 'CLI auth token:' prompt to 'Token:' and
improve spacing around the prompt.

- 'Failed to predict' → 'Failed to run prediction' in predict.go
- 'The inputs you passed to cog predict' → 'The inputs you passed' in
  predictor.go (shorter, less redundant since the user knows they ran cog)
- Add blank line after 'Running...' message in run.go for visual
  separation from Docker output

- Remove leading \n from 'Setting up...' message (prefix handles
  spacing), use separate console.Info('') for the blank line after
- Show 'Creating {filename}' (info, before write) instead of
  'Created {fullpath}' (success, after write) — less noisy, uses
  just the filename since the user knows their working directory

The 'Building Docker image...' message and surrounding blank lines are
user-facing concerns that belong in the CLI commands, not deep in
pkg/image/build.go. This lets each command control what it shows:

- cog build / cog push: show image name (user-chosen, meaningful)
- cog predict / cog train / cog run / cog serve: hide image name
  (ephemeral internal detail the user can't use)

Each CLI command now prints the message + blank line before calling
resolver.Build(), and the pre-ImageBuild blank lines are removed from
image/build.go.