Add mission-based target dV presets

[FennexFox]

Goal

Add mission-based target dV presets to Simulation Conditions.

The first public feedback suggested that the chart would be easier to use if common mission profiles provided rough target dV values. This should be a lightweight helper for the existing Target dV control, not a full chart preset.

Presets

• LEO Defense / non-Earth orbit — 2 km/s
• MEO to LEO — 4 km/s
• All Earth Defense — 8 km/s
• Deceleration Burn Intercept — 20 km/s
• Asteroid Assault — 30 km/s
• Jupiter Assault — 50 km/s
• Fast Asteroid Assault — 150 km/s
• Kuiper Belt Assault — 200 km/s
• Fast Kuiper Belt — 500 km/s

Suggested implementation

Add a Mission dV preset select under the existing Target dV control in Simulation Conditions.

Selecting a mission preset should:

• update state.targetDvKps
• update both Target dV range and number inputs
• re-render the chart
• leave dry mass, radiator, filters, selected metric, power view, module effects, and ship design assumptions unchanged

Manual Target dV edits should:

• keep working as before
• set the mission preset select to Custom when the current value does not exactly match a preset
• select the matching mission preset when the current value exactly matches one

Non-goals

• Do not create full chart presets for each mission.
• Do not overwrite dry mass, radiator, filters, categories, families, or ship design assumptions.
• Do not infer travel-time-optimal trajectories; these are rough gameplay presets only.

Acceptance criteria

• Simulation Conditions contains a Mission dV preset control near Target dV.
• Selecting each preset updates Target dV to the listed km/s value.
• Existing Target dV range and number inputs remain synchronized.
• Manual Target dV edits update the preset control to Custom unless the value exactly matches a preset.
• Chart re-renders after applying a mission preset.
• Existing chart presets and dry-mass/design presets continue to work.
• Korean and English UI strings are covered.
• Build and verification pass.