0.9.73b SPG Advanced Difficulty and new Vehicle "Chi-Ha Long Gun"

Hey Commanders! Here comes the 0.9.73b update!
A brand-new self-propelled gun, a new advanced challenge, a new garage feature, and lots of smaller changes. Let's take a look!

• "Chi-Ha Long Gun":
  A bizarre tank built by the navy, stuffing a 120 mm naval gun onto a light chassis!
  
• Comes with the unique affix "Reload with Spirit":
  Rapidly tap the "R" key to increase reload speed!
  

• The former "Anti-Concrete" affix has been renamed to "Semi Armour-Piercing": Shells can now penetrate obstacles.
  
• Weapons that currently have the "Semi Armour-Piercing" affix:
  
  
  
  • Chi-Ha Long Gun
    
  • KV-2
    
  • Karl Mortar
    

• Clear Difficulty 5 using 4 different SPGs to unlock the Chi-Ha Long Gun!
  
• Advanced challenge rules:
  
  
  
  • All HE shells and rockets now also deal damage to allies
    
  • Your gunfire noise now attracts enemies from a wide area
    
  • Explosion damage taken by enemies is reduced by 30%, but enemies hit by explosions are temporarily weakened
    
  • Enemy light tank quantity +20%
    
  • Enemy artillery positions are added to the map. They will bombard targets within enemy sight
    

• Added First-person mode to the garage:
  You can now exit your vehicle and freely walk around to observe it!
  
  
  
  
  
  
• All vehicles gained "Dazzle camouflage", unlocked at vehicle level 15
  
• Japanese vehicles gained "Brown camouflage" (And one German tank somehow got it as well)
  
• When a turret receives a reload speed buff, the UI will now display a clear color change
  
• Updated all in-game shell models
  

• Fixed an issue where the Snow Town Raid mission appeared far too frequently
  
• AI multi turret tanks will now notify their commander when a sub turret spots an enemy
  

💡 This is a Beta update. Please participate in testing by right-clicking on the game in Steam, selecting "Properties" → "Betas" → "Beta Participation"! Once everything's stable, it'll go live on the default branch.